Spectrophotometric techniques by which the absorption or emmision spectra of radiation from atoms are produced and analyzed.
The art or process of comparing photometrically the relative intensities of the light in different parts of the spectrum.
Determination of the spectra of ultraviolet absorption by specific molecules in gases or liquids, for example Cl2, SO2, NO2, CS2, ozone, mercury vapor, and various unsaturated compounds. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Spectrophotometry in the infrared region, usually for the purpose of chemical analysis through measurement of absorption spectra associated with rotational and vibrational energy levels of molecules. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Solid dosage forms, of varying weight, size, and shape, which may be molded or compressed, and which contain a medicinal substance in pure or diluted form. (Dorland, 28th ed)
A metallic element of atomic number 30 and atomic weight 65.38. It is a necessary trace element in the diet, forming an essential part of many enzymes, and playing an important role in protein synthesis and in cell division. Zinc deficiency is associated with ANEMIA, short stature, HYPOGONADISM, impaired WOUND HEALING, and geophagia. It is known by the symbol Zn.
An allotropic form of carbon that is used in pencils, as a lubricant, and in matches and explosives. It is obtained by mining and its dust can cause lung irritation.
The development and use of techniques and equipment to study or perform chemical reactions, with small quantities of materials, frequently less than a milligram or a milliliter.
A compound formed by the combination of hemoglobin and oxygen. It is a complex in which the oxygen is bound directly to the iron without causing a change from the ferrous to the ferric state.
Determination, by measurement or comparison with a standard, of the correct value of each scale reading on a meter or other measuring instrument; or determination of the settings of a control device that correspond to particular values of voltage, current, frequency or other output.
Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.
A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).
The rate dynamics in chemical or physical systems.
A heavy metal trace element with the atomic symbol Cu, atomic number 29, and atomic weight 63.55.
A metallic element that has the atomic number 13, atomic symbol Al, and atomic weight 26.98.
A tricarbocyanine dye that is used diagnostically in liver function tests and to determine blood volume and cardiac output.
A series of steps taken in order to conduct research.
The visually perceived property of objects created by absorption or reflection of specific wavelengths of light.
Chemicals and substances that impart color including soluble dyes and insoluble pigments. They are used in INKS; PAINTS; and as INDICATORS AND REAGENTS.
A soft, grayish metal with poisonous salts; atomic number 82, atomic weight 207.19, symbol Pb. (Dorland, 28th)
Substances used for the detection, identification, analysis, etc. of chemical, biological, or pathologic processes or conditions. Indicators are substances that change in physical appearance, e.g., color, at or approaching the endpoint of a chemical titration, e.g., on the passage between acidity and alkalinity. Reagents are substances used for the detection or determination of another substance by chemical or microscopical means, especially analysis. Types of reagents are precipitants, solvents, oxidizers, reducers, fluxes, and colorimetric reagents. (From Grant & Hackh's Chemical Dictionary, 5th ed, p301, p499)
A group of chemical elements that are needed in minute quantities for the proper growth, development, and physiology of an organism. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
A bile pigment that is a degradation product of HEME.
The measurement of the amplitude of the components of a complex waveform throughout the frequency range of the waveform. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Any technique by which an unknown color is evaluated in terms of standard colors. The technique may be visual, photoelectric, or indirect by means of spectrophotometry. It is used in chemistry and physics. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Method for determining the circulating blood volume by introducing a known quantity of foreign substance into the blood and determining its concentration some minutes later when thorough mixing has occurred. From these two values the blood volume can be calculated by dividing the quantity of injected material by its concentration in the blood at the time of uniform mixing. Generally expressed as cubic centimeters or liters per kilogram of body weight.
The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Measurement of the intensity and quality of fluorescence.
Chromatography on thin layers of adsorbents rather than in columns. The adsorbent can be alumina, silica gel, silicates, charcoals, or cellulose. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Inorganic compounds that contain magnesium as an integral part of the molecule.
The analysis of a chemical substance by inserting a sample into a carrier stream of reagent using a sample injection valve that propels the sample downstream where mixing occurs in a coiled tube, then passes into a flow-through detector and a recorder or other data handling device.
Dithionite. The dithionous acid ion and its salts.
Inorganic compounds that contain potassium as an integral part of the molecule.
A trace element that plays a role in glucose metabolism. It has the atomic symbol Cr, atomic number 24, and atomic weight 52. According to the Fourth Annual Report on Carcinogens (NTP85-002,1985), chromium and some of its compounds have been listed as known carcinogens.
The measurement of the density of a material by measuring the amount of light or radiation passing through (or absorbed by) the material.
An inorganic compound that is used as a source of iodine in thyrotoxic crisis and in the preparation of thyrotoxic patients for thyroidectomy. (From Dorland, 27th ed)
Metals with high specific gravity, typically larger than 5. They have complex spectra, form colored salts and double salts, have a low electrode potential, are mainly amphoteric, yield weak bases and weak acids, and are oxidizing or reducing agents (From Grant & Hackh's Chemical Dictionary, 5th ed)
Method of analyzing chemicals using automation.
A strong corrosive acid that is commonly used as a laboratory reagent. It is formed by dissolving hydrogen chloride in water. GASTRIC ACID is the hydrochloric acid component of GASTRIC JUICE.
A silver metallic element that exists as a liquid at room temperature. It has the atomic symbol Hg (from hydrargyrum, liquid silver), atomic number 80, and atomic weight 200.59. Mercury is used in many industrial applications and its salts have been employed therapeutically as purgatives, antisyphilitics, disinfectants, and astringents. It can be absorbed through the skin and mucous membranes which leads to MERCURY POISONING. Because of its toxicity, the clinical use of mercury and mercurials is diminishing.
A metallic element that has the atomic symbol Mg, atomic number 12, and atomic weight 24.31. It is important for the activity of many enzymes, especially those involved in OXIDATIVE PHOSPHORYLATION.
Tapping fluid from the subarachnoid space in the lumbar region, usually between the third and fourth lumbar vertebrae.
Inorganic or organic salts and esters of boric acid.
A plant genus of the family ASTERACEAE. Other plants called broom include CYTISUS; SPARTIUM; and BROMUS.
A metallic element with atomic symbol Fe, atomic number 26, and atomic weight 55.85. It is an essential constituent of HEMOGLOBINS; CYTOCHROMES; and IRON-BINDING PROTEINS. It plays a role in cellular redox reactions and in the transport of OXYGEN.
Proteins in the cerebrospinal fluid, normally albumin and globulin present in the ratio of 8 to 1. Increases in protein levels are of diagnostic value in neurological diseases. (Brain and Bannister's Clinical Neurology, 7th ed, p221)
The statistical reproducibility of measurements (often in a clinical context), including the testing of instrumentation or techniques to obtain reproducible results. The concept includes reproducibility of physiological measurements, which may be used to develop rules to assess probability or prognosis, or response to a stimulus; reproducibility of occurrence of a condition; and reproducibility of experimental results.
Tantalum. A rare metallic element, atomic number 73, atomic weight 180.948, symbol Ta. It is a noncorrosive and malleable metal that has been used for plates or disks to replace cranial defects, for wire sutures, and for making prosthetic devices. (Dorland, 28th ed)
The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.
The oxygen-carrying proteins of ERYTHROCYTES. They are found in all vertebrates and some invertebrates. The number of globin subunits in the hemoglobin quaternary structure differs between species. Structures range from monomeric to a variety of multimeric arrangements.
A basic science concerned with the composition, structure, and properties of matter; and the reactions that occur between substances and the associated energy exchange.
An element with atomic symbol Cd, atomic number 48, and atomic weight 114. It is a metal and ingestion will lead to CADMIUM POISONING.
The composition, conformation, and properties of atoms and molecules, and their reaction and interaction processes.
An element with atomic symbol O, atomic number 8, and atomic weight [15.99903; 15.99977]. It is the most abundant element on earth and essential for respiration.
The homogeneous mixtures formed by the mixing of a solid, liquid, or gaseous substance (solute) with a liquid (the solvent), from which the dissolved substances can be recovered by physical processes. (From Grant & Hackh's Chemical Dictionary, 5th ed)
A filament-like structure consisting of a shaft which projects to the surface of the SKIN from a root which is softer than the shaft and lodges in the cavity of a HAIR FOLLICLE. It is found on most surfaces of the body.
Inorganic or organic compounds containing trivalent iron.
The chemical and physical integrity of a pharmaceutical product.
A trace element with atomic symbol Mn, atomic number 25, and atomic weight 54.94. It is concentrated in cell mitochondria, mostly in the pituitary gland, liver, pancreas, kidney, and bone, influences the synthesis of mucopolysaccharides, stimulates hepatic synthesis of cholesterol and fatty acids, and is a cofactor in many enzymes, including arginase and alkaline phosphatase in the liver. (From AMA Drug Evaluations Annual 1992, p2035)
A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Elements of limited time intervals, contributing to particular results or situations.
Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.
Chemical compounds which pollute the water of rivers, streams, lakes, the sea, reservoirs, or other bodies of water.
Derivatives of the dimethylisoalloxazine (7,8-dimethylbenzo[g]pteridine-2,4(3H,10H)-dione) skeleton. Flavin derivatives serve an electron transfer function as ENZYME COFACTORS in FLAVOPROTEINS.
Chemical analysis based on the phenomenon whereby light, passing through a medium with dispersed particles of a different refractive index from that of the medium, is attenuated in intensity by scattering. In turbidimetry, the intensity of light transmitted through the medium, the unscattered light, is measured. In nephelometry, the intensity of the scattered light is measured, usually, but not necessarily, at right angles to the incident light beam.
Fractionation of a vaporized sample as a consequence of partition between a mobile gaseous phase and a stationary phase held in a column. Two types are gas-solid chromatography, where the fixed phase is a solid, and gas-liquid, in which the stationary phase is a nonvolatile liquid supported on an inert solid matrix.
Platinum. A heavy, soft, whitish metal, resembling tin, atomic number 78, atomic weight 195.09, symbol Pt. (From Dorland, 28th ed) It is used in manufacturing equipment for laboratory and industrial use. It occurs as a black powder (platinum black) and as a spongy substance (spongy platinum) and may have been known in Pliny's time as "alutiae".
A multisubunit enzyme complex containing CYTOCHROME A GROUP; CYTOCHROME A3; two copper atoms; and 13 different protein subunits. It is the terminal oxidase complex of the RESPIRATORY CHAIN and collects electrons that are transferred from the reduced CYTOCHROME C GROUP and donates them to molecular OXYGEN, which is then reduced to water. The redox reaction is simultaneously coupled to the transport of PROTONS across the inner mitochondrial membrane.
A chemical element having an atomic weight of 106.4, atomic number of 46, and the symbol Pd. It is a white, ductile metal resembling platinum, and following it in abundance and importance of applications. It is used in dentistry in the form of gold, silver, and copper alloys.
Concentration or quantity that is derived from the smallest measure that can be detected with reasonable certainty for a given analytical procedure.
A trace element with the atomic symbol Ni, atomic number 28, and atomic weight 58.69. It is a cofactor of the enzyme UREASE.
Relating to the size of solids.
Inorganic or organic oxy acids of sulfur which contain the RSO2(OH) radical.
A compound consisting of dark green crystals or crystalline powder, having a bronze-like luster. Solutions in water or alcohol have a deep blue color. Methylene blue is used as a bacteriologic stain and as an indicator. It inhibits GUANYLATE CYCLASE, and has been used to treat cyanide poisoning and to lower levels of METHEMOGLOBIN.
Bleeding into the intracranial or spinal SUBARACHNOID SPACE, most resulting from INTRACRANIAL ANEURYSM rupture. It can occur after traumatic injuries (SUBARACHNOID HEMORRHAGE, TRAUMATIC). Clinical features include HEADACHE; NAUSEA; VOMITING, nuchal rigidity, variable neurological deficits and reduced mental status.
An element with the atomic symbol Se, atomic number 34, and atomic weight 78.96. It is an essential micronutrient for mammals and other animals but is toxic in large amounts. Selenium protects intracellular structures against oxidative damage. It is an essential component of GLUTATHIONE PEROXIDASE.
A trace element that is a component of vitamin B12. It has the atomic symbol Co, atomic number 27, and atomic weight 58.93. It is used in nuclear weapons, alloys, and pigments. Deficiency in animals leads to anemia; its excess in humans can lead to erythrocytosis.
Hemeproteins whose characteristic mode of action involves transfer of reducing equivalents which are associated with a reversible change in oxidation state of the prosthetic group. Formally, this redox change involves a single-electron, reversible equilibrium between the Fe(II) and Fe(III) states of the central iron atom (From Enzyme Nomenclature, 1992, p539). The various cytochrome subclasses are organized by the type of HEME and by the wavelength range of their reduced alpha-absorption bands.
A basic element found in nearly all organized tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.
The separation of particles from a suspension by passage through a filter with very fine pores. In ultrafiltration the separation is accomplished by convective transport; in DIALYSIS separation relies instead upon differential diffusion. Ultrafiltration occurs naturally and is a laboratory procedure. Artificial ultrafiltration of the blood is referred to as HEMOFILTRATION or HEMODIAFILTRATION (if combined with HEMODIALYSIS).
Carbon monoxide (CO). A poisonous colorless, odorless, tasteless gas. It combines with hemoglobin to form carboxyhemoglobin, which has no oxygen carrying capacity. The resultant oxygen deprivation causes headache, dizziness, decreased pulse and respiratory rates, unconsciousness, and death. (From Merck Index, 11th ed)
A technique applicable to the wide variety of substances which exhibit paramagnetism because of the magnetic moments of unpaired electrons. The spectra are useful for detection and identification, for determination of electron structure, for study of interactions between molecules, and for measurement of nuclear spins and moments. (From McGraw-Hill Encyclopedia of Science and Technology, 7th edition) Electron nuclear double resonance (ENDOR) spectroscopy is a variant of the technique which can give enhanced resolution. Electron spin resonance analysis can now be used in vivo, including imaging applications such as MAGNETIC RESONANCE IMAGING.
Drugs intended for human or veterinary use, presented in their finished dosage form. Included here are materials used in the preparation and/or formulation of the finished dosage form.
A thiazide diuretic often considered the prototypical member of this class. It reduces the reabsorption of electrolytes from the renal tubules. This results in increased excretion of water and electrolytes, including sodium, potassium, chloride, and magnesium. It is used in the treatment of several disorders including edema, hypertension, diabetes insipidus, and hypoparathyroidism.
The monitoring of the level of toxins, chemical pollutants, microbial contaminants, or other harmful substances in the environment (soil, air, and water), workplace, or in the bodies of people and animals present in that environment.
A metallic element with the atomic symbol Mo, atomic number 42, and atomic weight 95.94. It is an essential trace element, being a component of the enzymes xanthine oxidase, aldehyde oxidase, and nitrate reductase. (From Dorland, 27th ed)
A conjugated protein which is the oxygen-transporting pigment of muscle. It is made up of one globin polypeptide chain and one heme group.
Theoretical representations that simulate the behavior or activity of chemical processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.
The range or frequency distribution of a measurement in a population (of organisms, organs or things) that has not been selected for the presence of disease or abnormality.
The application of scientific knowledge or technology to pharmacy and the pharmaceutical industry. It includes methods, techniques, and instrumentation in the manufacture, preparation, compounding, dispensing, packaging, and storing of drugs and other preparations used in diagnostic and determinative procedures, and in the treatment of patients.
A system for verifying and maintaining a desired level of quality in a product or process by careful planning, use of proper equipment, continued inspection, and corrective action as required. (Random House Unabridged Dictionary, 2d ed)
Inorganic or organic compounds that contain divalent iron.
Insoluble polymers of TYROSINE derivatives found in and causing darkness in skin (SKIN PIGMENTATION), hair, and feathers providing protection against SUNBURN induced by SUNLIGHT. CAROTENES contribute yellow and red coloration.
Inorganic salts of HYDROGEN CYANIDE containing the -CN radical. The concept also includes isocyanides. It is distinguished from NITRILES, which denotes organic compounds containing the -CN radical.
A spectroscopic technique in which a range of wavelengths is presented simultaneously with an interferometer and the spectrum is mathematically derived from the pattern thus obtained.
A noninvasive technique that uses the differential absorption properties of hemoglobin and myoglobin to evaluate tissue oxygenation and indirectly can measure regional hemodynamics and blood flow. Near-infrared light (NIR) can propagate through tissues and at particular wavelengths is differentially absorbed by oxygenated vs. deoxygenated forms of hemoglobin and myoglobin. Illumination of intact tissue with NIR allows qualitative assessment of changes in the tissue concentration of these molecules. The analysis is also used to determine body composition.
Liquids that dissolve other substances (solutes), generally solids, without any change in chemical composition, as, water containing sugar. (Grant & Hackh's Chemical Dictionary, 5th ed)
The process by which ELECTRONS are transported from a reduced substrate to molecular OXYGEN. (From Bennington, Saunders Dictionary and Encyclopedia of Laboratory Medicine and Technology, 1984, p270)
Studies determining the effectiveness or value of processes, personnel, and equipment, or the material on conducting such studies. For drugs and devices, CLINICAL TRIALS AS TOPIC; DRUG EVALUATION; and DRUG EVALUATION, PRECLINICAL are available.
The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.
An analytical method used in determining the identity of a chemical based on its mass using mass analyzers/mass spectrometers.
Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.
The physical or physiological processes by which substances, tissue, cells, etc. take up or take in other substances or energy.
Volume of circulating BLOOD. It is the sum of the PLASMA VOLUME and ERYTHROCYTE VOLUME.
Transparent, tasteless crystals found in nature as agate, amethyst, chalcedony, cristobalite, flint, sand, QUARTZ, and tridymite. The compound is insoluble in water or acids except hydrofluoric acid.
That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.
Concentrated pharmaceutical preparations of plants obtained by removing active constituents with a suitable solvent, which is evaporated away, and adjusting the residue to a prescribed standard.
The rate at which oxygen is used by a tissue; microliters of oxygen STPD used per milligram of tissue per hour; the rate at which oxygen enters the blood from alveolar gas, equal in the steady state to the consumption of oxygen by tissue metabolism throughout the body. (Stedman, 25th ed, p346)
Stable elementary particles having the smallest known negative charge, present in all elements; also called negatrons. Positively charged electrons are called positrons. The numbers, energies and arrangement of electrons around atomic nuclei determine the chemical identities of elements. Beams of electrons are called CATHODE RAYS.
Particles consisting of aggregates of molecules held loosely together by secondary bonds. The surface of micelles are usually comprised of amphiphatic compounds that are oriented in a way that minimizes the energy of interaction between the micelle and its environment. Liquids that contain large numbers of suspended micelles are referred to as EMULSIONS.
A basis of value established for the measure of quantity, weight, extent or quality, e.g. weight standards, standard solutions, methods, techniques, and procedures used in diagnosis and therapy.
The facilitation of a chemical reaction by material (catalyst) that is not consumed by the reaction.
A chemical system that functions to control the levels of specific ions in solution. When the level of hydrogen ion in solution is controlled the system is called a pH buffer.
Naturally occurring or synthetic substances that inhibit or retard the oxidation of a substance to which it is added. They counteract the harmful and damaging effects of oxidation in animal tissues.
A colorless, flammable liquid used in the manufacture of FORMALDEHYDE and ACETIC ACID, in chemical synthesis, antifreeze, and as a solvent. Ingestion of methanol is toxic and may cause blindness.
The ability of a substance to be dissolved, i.e. to form a solution with another substance. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
The study of chemical changes resulting from electrical action and electrical activity resulting from chemical changes.
Spectroscopic method of measuring the magnetic moment of elementary particles such as atomic nuclei, protons or electrons. It is employed in clinical applications such as NMR Tomography (MAGNETIC RESONANCE IMAGING).
Nicotinamide adenine dinucleotide phosphate. A coenzyme composed of ribosylnicotinamide 5'-phosphate (NMN) coupled by pyrophosphate linkage to the 5'-phosphate adenosine 2',5'-bisphosphate. It serves as an electron carrier in a number of reactions, being alternately oxidized (NADP+) and reduced (NADPH). (Dorland, 27th ed)
Chinese herbal or plant extracts which are used as drugs to treat diseases or promote general well-being. The concept does not include synthesized compounds manufactured in China.
The color-furnishing portion of hemoglobin. It is found free in tissues and as the prosthetic group in many hemeproteins.
A shiny gray element with atomic symbol As, atomic number 33, and atomic weight 75. It occurs throughout the universe, mostly in the form of metallic arsenides. Most forms are toxic. According to the Fourth Annual Report on Carcinogens (NTP 85-002, 1985), arsenic and certain arsenic compounds have been listed as known carcinogens. (From Merck Index, 11th ed)
The dialdehyde of malonic acid.
Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.
The general name for a group of fat-soluble pigments found in green, yellow, and leafy vegetables, and yellow fruits. They are aliphatic hydrocarbons consisting of a polyisoprene backbone.
A rigorously mathematical analysis of energy relationships (heat, work, temperature, and equilibrium). It describes systems whose states are determined by thermal parameters, such as temperature, in addition to mechanical and electromagnetic parameters. (From Hawley's Condensed Chemical Dictionary, 12th ed)
A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.
The products of chemical reactions that result in the addition of extraneous chemical groups to DNA.
Forms to which substances are incorporated to improve the delivery and the effectiveness of drugs. Drug carriers are used in drug-delivery systems such as the controlled-release technology to prolong in vivo drug actions, decrease drug metabolism, and reduce drug toxicity. Carriers are also used in designs to increase the effectiveness of drug delivery to the target sites of pharmacological actions. Liposomes, albumin microspheres, soluble synthetic polymers, DNA complexes, protein-drug conjugates, and carrier erythrocytes among others have been employed as biodegradable drug carriers.
Electropositive chemical elements characterized by ductility, malleability, luster, and conductance of heat and electricity. They can replace the hydrogen of an acid and form bases with hydroxyl radicals. (Grant & Hackh's Chemical Dictionary, 5th ed)
A group of cytochromes with covalent thioether linkages between either or both of the vinyl side chains of protoheme and the protein. (Enzyme Nomenclature, 1992, p539)
The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.
An oxidoreductase that catalyzes the reaction between superoxide anions and hydrogen to yield molecular oxygen and hydrogen peroxide. The enzyme protects the cell against dangerous levels of superoxide. EC
An oxidoreductase that catalyzes the conversion of HYDROGEN PEROXIDE to water and oxygen. It is present in many animal cells. A deficiency of this enzyme results in ACATALASIA.
The class of all enzymes catalyzing oxidoreduction reactions. The substrate that is oxidized is regarded as a hydrogen donor. The systematic name is based on donor:acceptor oxidoreductase. The recommended name will be dehydrogenase, wherever this is possible; as an alternative, reductase can be used. Oxidase is only used in cases where O2 is the acceptor. (Enzyme Nomenclature, 1992, p9)
Differential thermal analysis in which the sample compartment of the apparatus is a differential calorimeter, allowing an exact measure of the heat of transition independent of the specific heat, thermal conductivity, and other variables of the sample.
The testing of materials and devices, especially those used for PROSTHESES AND IMPLANTS; SUTURES; TISSUE ADHESIVES; etc., for hardness, strength, durability, safety, efficacy, and biocompatibility.
The deductive study of shape, quantity, and dependence. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Chemicals that bind to and remove ions from solutions. Many chelating agents function through the formation of COORDINATION COMPLEXES with METALS.
A family of zinc-containing enzymes that catalyze the reversible hydration of carbon dioxide. They play an important role in the transport of CARBON DIOXIDE from the tissues to the LUNG. EC
Compounds containing the -SH radical.
A condensation product of riboflavin and adenosine diphosphate. The coenzyme of various aerobic dehydrogenases, e.g., D-amino acid oxidase and L-amino acid oxidase. (Lehninger, Principles of Biochemistry, 1982, p972)
The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.
An enzyme system that catalyzes the fixing of nitrogen in soil bacteria and blue-green algae (CYANOBACTERIA). EC
A barbituric acid derivative that acts as a nonselective central nervous system depressant. It potentiates GAMMA-AMINOBUTYRIC ACID action on GABA-A RECEPTORS, and modulates chloride currents through receptor channels. It also inhibits glutamate induced depolarizations.
Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)
Polymers of ETHYLENE OXIDE and water, and their ethers. They vary in consistency from liquid to solid depending on the molecular weight indicated by a number following the name. They are used as SURFACTANTS, dispersing agents, solvents, ointment and suppository bases, vehicles, and tablet excipients. Some specific groups are NONOXYNOLS, OCTOXYNOLS, and POLOXAMERS.
Chemistry dealing with the composition and preparation of agents having PHARMACOLOGIC ACTIONS or diagnostic use.
A change from planar to elliptic polarization when an initially plane-polarized light wave traverses an optically active medium. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
The presence in food of harmful, unpalatable, or otherwise objectionable foreign substances, e.g. chemicals, microorganisms or diluents, before, during, or after processing or storage.
A disturbance in the prooxidant-antioxidant balance in favor of the former, leading to potential damage. Indicators of oxidative stress include damaged DNA bases, protein oxidation products, and lipid peroxidation products (Sies, Oxidative Stress, 1991, pxv-xvi).
A six carbon compound related to glucose. It is found naturally in citrus fruits and many vegetables. Ascorbic acid is an essential nutrient in human diets, and necessary to maintain connective tissue and bone. Its biologically active form, vitamin C, functions as a reducing agent and coenzyme in several metabolic pathways. Vitamin C is considered an antioxidant.
Large, hoofed mammals of the family EQUIDAE. Horses are active day and night with most of the day spent seeking and consuming food. Feeding peaks occur in the early morning and late afternoon, and there are several daily periods of rest.
Systems for the delivery of drugs to target sites of pharmacological actions. Technologies employed include those concerning drug preparation, route of administration, site targeting, metabolism, and toxicity.
The property of emitting radiation while being irradiated. The radiation emitted is usually of longer wavelength than that incident or absorbed, e.g., a substance can be irradiated with invisible radiation and emit visible light. X-ray fluorescence is used in diagnosis.
A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.
Salts of nitrous acid or compounds containing the group NO2-. The inorganic nitrites of the type MNO2 (where M=metal) are all insoluble, except the alkali nitrites. The organic nitrites may be isomeric, but not identical with the corresponding nitro compounds. (Grant & Hackh's Chemical Dictionary, 5th ed)
A microanalytical technique combining mass spectrometry and gas chromatography for the qualitative as well as quantitative determinations of compounds.
Single preparations containing two or more active agents, for the purpose of their concurrent administration as a fixed dose mixture.
A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).
A strong oxidizing agent used in aqueous solution as a ripening agent, bleach, and topical anti-infective. It is relatively unstable and solutions deteriorate over time unless stabilized by the addition of acetanilide or similar organic materials.
Positively charged atoms, radicals or groups of atoms which travel to the cathode or negative pole during electrolysis.
A chelating agent that sequesters a variety of polyvalent cations such as CALCIUM. It is used in pharmaceutical manufacturing and as a food additive.
The diversion of RADIATION (thermal, electromagnetic, or nuclear) from its original path as a result of interactions or collisions with atoms, molecules, or larger particles in the atmosphere or other media. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Electron-accepting molecules in chemical reactions in which electrons are transferred from one molecule to another (OXIDATION-REDUCTION).
A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.
Factors that bind to RNA POLYMERASE III and aid in transcription. They include the assembly factors TFIIIA and TFIIIC and the initiation factor TFIIIB. All combine to form a preinitiation complex at the promotor that directs the binding of RNA POLYMERASE III.
The process of cleaving a chemical compound by the addition of a molecule of water.
A hemeprotein from leukocytes. Deficiency of this enzyme leads to a hereditary disorder coupled with disseminated moniliasis. It catalyzes the conversion of a donor and peroxide to an oxidized donor and water. EC
Presence of warmth or heat or a temperature notably higher than an accustomed norm.
A coenzyme composed of ribosylnicotinamide 5'-diphosphate coupled to adenosine 5'-phosphate by pyrophosphate linkage. It is found widely in nature and is involved in numerous enzymatic reactions in which it serves as an electron carrier by being alternately oxidized (NAD+) and reduced (NADH). (Dorland, 27th ed)
The parts of a macromolecule that directly participate in its specific combination with another molecule.
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.
Benzene derivatives that include one or more hydroxyl groups attached to the ring structure.
The complete absence, or (loosely) the paucity, of gaseous or dissolved elemental oxygen in a given place or environment. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)
Inorganic salts of phosphoric acid.
Electron microscopy in which the ELECTRONS or their reaction products that pass down through the specimen are imaged below the plane of the specimen.
The exposure to potentially harmful chemical, physical, or biological agents in the environment or to environmental factors that may include ionizing radiation, pathogenic organisms, or toxic chemicals.
An enzyme catalyzing the oxidation of 2 moles of glutathione in the presence of hydrogen peroxide to yield oxidized glutathione and water. EC
A major protein in the BLOOD. It is important in maintaining the colloidal osmotic pressure and transporting large organic molecules.
A superfamily of hundreds of closely related HEMEPROTEINS found throughout the phylogenetic spectrum, from animals, plants, fungi, to bacteria. They include numerous complex monooxygenases (MIXED FUNCTION OXYGENASES). In animals, these P-450 enzymes serve two major functions: (1) biosynthesis of steroids, fatty acids, and bile acids; (2) metabolism of endogenous and a wide variety of exogenous substrates, such as toxins and drugs (BIOTRANSFORMATION). They are classified, according to their sequence similarities rather than functions, into CYP gene families (>40% homology) and subfamilies (>59% homology). For example, enzymes from the CYP1, CYP2, and CYP3 gene families are responsible for most drug metabolism.
Property of membranes and other structures to permit passage of light, heat, gases, liquids, metabolites, and mineral ions.
Expanded structures, usually green, of vascular plants, characteristically consisting of a bladelike expansion attached to a stem, and functioning as the principal organ of photosynthesis and transpiration. (American Heritage Dictionary, 2d ed)
Microscopy in which the object is examined directly by an electron beam scanning the specimen point-by-point. The image is constructed by detecting the products of specimen interactions that are projected above the plane of the sample, such as backscattered electrons. Although SCANNING TRANSMISSION ELECTRON MICROSCOPY also scans the specimen point by point with the electron beam, the image is constructed by detecting the electrons, or their interaction products that are transmitted through the sample plane, so that is a form of TRANSMISSION ELECTRON MICROSCOPY.
The relationship between the dose of an administered drug and the response of the organism to the drug.
Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).
The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.
Nanometer-sized particles that are nanoscale in three dimensions. They include nanocrystaline materials; NANOCAPSULES; METAL NANOPARTICLES; DENDRIMERS, and QUANTUM DOTS. The uses of nanoparticles include DRUG DELIVERY SYSTEMS and cancer targeting and imaging.
A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.
A statistical technique that isolates and assesses the contributions of categorical independent variables to variation in the mean of a continuous dependent variable.
Measurable and quantifiable biological parameters (e.g., specific enzyme concentration, specific hormone concentration, specific gene phenotype distribution in a population, presence of biological substances) which serve as indices for health- and physiology-related assessments, such as disease risk, psychiatric disorders, environmental exposure and its effects, disease diagnosis, metabolic processes, substance abuse, pregnancy, cell line development, epidemiologic studies, etc.
Agents that emit light after excitation by light. The wave length of the emitted light is usually longer than that of the incident light. Fluorochromes are substances that cause fluorescence in other substances, i.e., dyes used to mark or label other compounds with fluorescent tags.
The concentration of osmotically active particles in solution expressed in terms of osmoles of solute per liter of solution. Osmolality is expressed in terms of osmoles of solute per kilogram of solvent.
The exposure to potentially harmful chemical, physical, or biological agents that occurs as a result of one's occupation.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
Stable elementary particles having the smallest known positive charge, found in the nuclei of all elements. The proton mass is less than that of a neutron. A proton is the nucleus of the light hydrogen atom, i.e., the hydrogen ion.
The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).
Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.

Identification and characterization of a recombinant metallothionein protein from a marine alga, Fucus vesiculosus. (1/1258)

A cDNA library was constructed from macroalgae adapted to prolonged elevated environmental copper levels. To investigate the possible existence of a metallothionein (MT) gene, the library was screened with degenerate probes designed using plant MT cysteine-rich motifs. A gene was identified (1229 bp) with a putative open reading frame (204 bp) encoding a 67-amino-acid protein exhibiting several characteristic features of MT proteins, including 16 cysteine residues (24%) and only one aromatic residue. Although the protein sequence showed high identity with plant and invertebrate MTs, it contained a unique 'linker' region (14 amino acid residues) between the two putative metal-binding domains which contained no cysteine residues. This extended linker is larger than the tripeptide found in archetypal vertebrate MTs, but does not conform either with the 40-amino-acid linkers commonly found in plant MT sequences. An S-peptide Fucus MT fusion protein expressed in Escherichia coli exhibited a relative molecular mass of approximately 14 kDa. The recombinant fusion bound seven Cd ions, of which 50% were dissociated at pH 4.1. Under anaerobic conditions, the Cd ions were displaced by Cu(I), which associated with the protein at a ratio of 13:1. Laboratory exposure of F. vesiculosus to elevated copper resulted in induction of the MT gene. Thus this paper describes, for the first time, an MT gene identified from macroalgae which is induced by copper exposure and whose encoded protein product binds cadmium and copper.  (+info)

Negligible amount of copper in hepatic L-tryptophan 2,3-dioxygenase. (2/1258)

During the purification of L-tryptophan 2,3-dioxygenase, a protohemoprotein from rat liver, both copper and heme contents of the preparations were found to be progressively increased as purification proceeded. However, the greater part of copper was removed in the late stages of the purification giving a copper to heme ratio less than 0.4. The small amounts of copper could further be reduced by one-half, by a mild treatment of enzyme with chelators such as ethylenedi aminetetraacetate, without any accompanying decrease in enzymatic activity. Since the turnover number of these enzyme preparations expressed per mol of enzyme-bound heme, 200 to 277 min-1 at 25 degrees, were either comparable to or slightly higher than those reported with homogeneous enzyme preparations, the heme in the preparation was considered to be of fully active L-tryptophan 2,3-dioxygenase and, therefore, such a small ratio of copper to heme, 0.1 to 0.3, indicated that copper is not a constituent of L-tryptophan 2,3-dioxygenase of rat liver. The findings were thus inconsistent with the results of Brady et al. (Brady, F. O., Monaco, M. E. Forman, H. J. Schutz, G., and Feigelson, P. (1972) J. Biol. Chem. 247, 7915-7922), who found that L-tryptophan 2,3-dioxygenase contained 2 g atoms of copper and 2 mol of heme/mol of enzyme. Possible reasons for this discrepancy have been discussed.  (+info)

Ruminant placental lactogens act as antagonists to homologous growth hormone receptors and as agonists to human or rabbit growth hormone receptors. (3/1258)

Growth hormone receptor (GHR)-mediated activity of ruminant placental lactogens (PLs) and ovine (o) GH was compared, using cells transfected with full size human (h), rabbit (rb), and oGHRs. All three PLs acted as agonists in heterologous bioassays, whereas in homologous bioassays in cells transfected with oGHRs they antagonized the oGH activity. Despite these differences, oGH and PLs bound with similar affinity to the oGHR extracellular domain (oGHR-ECD), indicating that the binding occurs through hormone site I. Gel filtration of complexes between oPL and oGHR-ECD showed a 1:1 stoichiometry, confirming this conclusion. The oPL T185D and bPL T188D, which exhibited weak biological activity mediated through GHRs, behaved as site I antagonists, whereas oPL G130R and bPL G133R formed a 1:1 complex with GHR-ECDs and bound to h/rb/oGHR-ECDs with affinity similar to that of wild-type oPL. They had no agonistic activity in all models transfected with h/rb and oGHRs, but were antagonistic to all of them. In conclusion, ruminant PLs antagonize the activity of oGH in homologous systems, because they cannot homodimerize oGHRs, whereas in heterologous systems they act as agonists. The structural analysis hints that minor differences in the sequence of the GHR-ECDs may account for this difference. Since the initial step in the activity transduced through cytokine/hemapoietic receptors family is receptor homodimerization or heterodimerization, we suggest that the question of homologous versus heterologous interactions should be reexamined.  (+info)

Transient and steady-state kinetics of the oxidation of substituted benzoic acid hydrazides by myeloperoxidase. (4/1258)

Myeloperoxidase is the most abundant protein in neutrophils and catalyzes the production of hypochlorous acid. This potent oxidant plays a central role in microbial killing and inflammatory tissue damage. 4-Aminobenzoic acid hydrazide (ABAH) is a mechanism-based inhibitor of myeloperoxidase that is oxidized to radical intermediates that cause enzyme inactivation. We have investigated the mechanism by which benzoic acid hydrazides (BAH) are oxidized by myeloperoxidase, and we have determined the features that enable them to inactivate the enzyme. BAHs readily reduced compound I of myeloperoxidase. The rate constants for these reactions ranged from 1 to 3 x 10(6) M-1 s-1 (15 degrees C, pH 7.0) and were relatively insensitive to the substituents on the aromatic ring. Rate constants for reduction of compound II varied between 6.5 x 10(5) M-1 s-1 for ABAH and 1.3 x 10(3) M-1 s-1 for 4-nitrobenzoic acid hydrazide (15 degrees C, pH 7.0). Reduction of both compound I and compound II by BAHs adhered to the Hammett rule, and there were significant correlations with Brown-Okamoto substituent constants. This indicates that the rates of these reactions were simply determined by the ease of oxidation of the substrates and that the incipient free radical carried a positive charge. ABAH was oxidized by myeloperoxidase without added hydrogen peroxide because it underwent auto-oxidation. Although BAHs generally reacted rapidly with compound II, they should be poor peroxidase substrates because the free radicals formed during peroxidation converted myeloperoxidase to compound III. We found that the reduction of ferric myeloperoxidase by BAH radicals was strongly influenced by Hansch's hydrophobicity constants. BAHs containing more hydrophilic substituents were more effective at converting the enzyme to compound III. This implies that BAH radicals must hydrogen bond to residues in the distal heme pocket before they can reduce the ferric enzyme. Inactivation of myeloperoxidase by BAHs was related to how readily they were oxidized, but there was no correlation with their rate constants for reduction of compounds I or II. We propose that BAHs destroy the heme prosthetic groups of the enzyme by reducing a ferrous myeloperoxidase-hydrogen peroxide complex.  (+info)

Release of copper ions from the familial amyotrophic lateral sclerosis-associated Cu,Zn-superoxide dismutase mutants. (5/1258)

Point mutations of Cu,Zn-superoxide dismutase (SOD) have been linked to familial amyotrophic lateral sclerosis (FALS). We reported that the Swedish FALS Cu,Zn-SOD mutant, D90A, exhibited an enhanced hydroxyl radical-generating activity, while its dismutation activity was identical to that of the wild-type enzyme (Kim et al. 1998a; 1998b). Transgenic mice that express a mutant Cu,Zn-SOD, Gly93 --> Ala (G93A), have been shown to develop amyotrophic lateral sclerosis (ALS) symptoms. We cloned the cDNA for the FALS G93A mutant, overexpressed the protein in E. coli cells, purified the protein, and studied its enzymic activities. Our results showed that the G93A, the D90A, and the wild-type enzymes have identical dismutation activity. However, the hydroxyl radical-generating activity of the G93A mutant was enhanced relative to those of the D90A and the wild-type enzyme (wild-type < D90A < G93A). These higher free radical-generating activities of mutants facilitated the release of copper ions from their own molecules (wild-type < D90A < G93A). The released copper ions can enhance the Fenton-like reaction to produce hydroxyl radicals and play a major role in the oxidative damage of macromolecules. Thus, the FALS symptoms may be associated with the enhancements in both the free radical-generating activity and the releasing of copper ions from the mutant enzyme.  (+info)

Determination of the stoichiometry and strength of binding of xanthophylls to the photosystem II light harvesting complexes. (6/1258)

Xanthophylls have a crucial role in the structure and function of the light harvesting complexes of photosystem II (LHCII) in plants. The binding of xanthophylls to LHCII has been investigated, particularly with respect to the xanthophyll cycle carotenoids violaxanthin and zeaxanthin. It was found that most of the violaxanthin pool was loosely bound to the major complex and could be removed by mild detergent treatment. Gentle solubilization of photosystem II particles and thylakoids allowed the isolation of complexes, including a newly described oligomeric preparation, enriched in trimers, that retained all of the in vivo violaxanthin pool. It was estimated that each LHCII monomer can bind at least one violaxanthin. The extent to which different pigments can be removed from LHCII indicated that the relative strength of binding was chlorophyll b > neoxanthin > chlorophyll a > lutein > zeaxanthin > violaxanthin. The xanthophyll binding sites are of two types: internal sites binding lutein and peripheral sites binding neoxanthin and violaxanthin. In CP29, a minor LHCII, both a lutein site and the neoxanthin site can be occupied by violaxanthin. Upon activation of the violaxanthin de-epoxidase, the highest de-epoxidation state was found for the main LHCII component and the lowest for CP29, suggesting that only violaxanthin loosely bound to LHCII is available for de-epoxidation.  (+info)

Interference in the quantitation of methylated arsenic species in human urine. (7/1258)

The aim of this paper is to report on the presence of chemical interferences in the quantitation of methylated arsenic species in human urine when using a method based on selective volatile arsine species generation, chromatographic separation, and hydride generation atomic absorption spectrometry (HGAAS) detection. An abnormal profile of methylated arsenic species characterized by the absence of the peak corresponding to dimethylarsinic acid (DMA) was observed in urine from some individuals exposed to arsenic via drinking water and living in rural communities of northwestern Argentina. The absence of this peak persisted even after the addition of known amounts of DMA to the samples. However, the DMA peak appeared after urine digestion with hydrochloric acid (2M). Samples showing interferences were provided by individuals who had mate consumption and coca-leaf chewing habits. Because the relative proportions of methylated arsenic species present in urine have been used to evaluate the efficiency of the methylation process, interferences in the formation or detection of methylarsines may cause underestimation of As exposure and also lead to erroneous conclusions about relative biomethylation efficiencies. Therefore, we recommend that urine samples should be digested with 2M HCl before performing speciation analysis using HGAA techniques. Further studies on the impact of this type of interferences on other arsenic speciation methods are also required.  (+info)

Determination of tin, vanadium, iron, and molybdenum in various matrices by atomic absorption spectrometry using a simultaneous liquid-liquid extraction procedure. (8/1258)

An atomic-absorption spectrometric method is described for the determination of tin, vanadium, iron, and molybdenum in two certified reference materials, food samples, and petroleum crude. After treatment with acids, these elements are separated from matrix elements by simultaneous solvent extraction of 5,5'-methylenedisalicylohydroxamic acid complexes from HCl/NaClO4 solution into an isobutyl methyl ketone/tributyl phosphate solution. The detection limits range from 0.018 to 0.19 microg/mL (n = 3), and the relative standard deviations do not exceed 2.0% at levels of 0.5, 0.6, 2.0, and 7.0 microg/mL of Fe, Mo, V, and Sn, respectively. The method is selective and suffers only from interference by Zr(IV), Ti(IV), Th(IV), W(VI), PO4(3-), and F-.  (+info)

E1834-18 Standard Test Method for Analysis of Nickel Alloys by Graphite Furnace Atomic Absorption Spectrometry lead content~ graphite furnace atomic absorption spectrometry~
C1466-00(2020) Standard Test Method for Graphite Furnace Atomic Absorption Spectrometric Determination of Lead and Cadmium Extracted From Ceramic Foodware
A graphite furnace atomic absorption spectrometry method has been developed for the quantitative determination of submicromolar endogenous concentration of lithium in human plasma and urine using pyrolitically-coated graphite tubes in combination with ammonium nitrate matrix modification. This latter treatment could not completely abolish the interferences caused by the matrix, notably in urine samples. The variability of the urinary matrices required an additional standardization procedure by solid-phase extraction on strongly acidic cation exchange cartridges. Matrix-matched samples were used for the establishment of calibration curves with the addition-calibration method. Calibration curves were linear up to 0.72 mumol/l (1.0 | r2 | 0.99). The described method enables accurate measurements of trace-lithium in biological samples at concentrations down to 0.03 mumol/l with intra- and inter-day variabilities < 10%. The method was applied to the determination of trace-lithium levels in
Application Note 43060. The iCE 3500 Atomic Absorption Spectrometer is the ideal solution for the analysis of major, minor and toxic elements in honey. The
A brief review is given of major advances in graphite furnace atomic absorption spectrometry over the last decade. Emphasis is placed on a method for the determination of alkaline earth and rare earth elements by a modified stabilised temperature platform furnace technique and a computerised method for the curvatur
Noller, BN (1978) Development and some applications of techniques for the determination of trace metals by furnace atomic absorption spectrometry. PhD thesis, University of Tasmania. ...
TY - CHAP. T1 - Vapour phase decomposition graphite furnace atomic absorption spectroscopy (VPD-GFAAS) analysis of Na, Mg and Al on silicon wafer surfaces. AU - Saloniemi, Heini. AU - Hintsala, Jouko. AU - Visti, Taru. AU - Eränen, Simo. PY - 2000. Y1 - 2000. M3 - Conference abstract in proceedings. BT - Kemian Päivät - Finnish Chemical Congress and Exhibition 2000. PB - Association of Finnish Chemical Societies. T2 - Kemian Päivät 2000. Y2 - 15 November 2000 through 17 November 2000. ER - ...
The technique was evaluated for decomposing biological st … Curatola CJ, Grunder FI, Moffitt AE Jr. A modified hydride generation, atomic absorption spectrophotometric (AAS) method for the analysis of total arsenic in hair has been developed to evaluate occupational exposures to arsenic. Hydride Generation Atomic Absorption Spectrometry is divided into two parts, with the theoretical background and experimental approach covered in Part I. Hydride Generation AAS nptelhrd Loading... Atomic Absorption Spectroscopy/Atomic Absorption Spectrometry/AAS - Duration: … selenium determination by hydride generation atomic absorption spectrophotometry (HG-AAS) in full blood, blood plasma and serum, the liver, skeletal muscle tissue, the myocardium, and the kidneys after wet mineralization of samples in a closed nitric acid and hydrogen peroxide system Electrochemical hydride generation (EcHG) as a sample introduction system for determination of zinc was developed. Change to nitrous oxide/acetylene flame. ...
Issuu is a digital publishing platform that makes it simple to publish magazines, catalogs, newspapers, books, and more online. Easily share your publications and get them in front of Issuus millions of monthly readers. Title: Atomic Absorption Spectrometer, Author: Atul Badola, Name: Atomic Absorption Spectrometer, Length: 6 pages, Page: 1, Published: 2011-01-02
AA320N Atomic Absorption Spectrophotometer using dual-beam reflection optical system, to do flame absorption emission, graphite furnace atomic absorption
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hydrochloride and indapamide via their chloride contents and captopril via its sulphur content. In case of oxprenolol hydrochloride, an excess of standard silver nitrate was added, the precipitated silver chloride was centrifuged and the silver contents of both the precipitate and the decanted solution were determined by atomic absorption spectrophotometry. In case of indapamide, oxygen flask combustion method was first carried out. Captopril was ashed using oxygen flask combustion method, followed by adding a known excess of barium chloride and the precipitated barium sulfate was centrifuged. The excess barium chloride in the decanted solution was determined by atomic absorption spectrophotometry ...
Methods for the complete characterization of liposomes prepared by ether-injection are described in detail. The validity of atomic absorption spectrophotometry Ior measuring markers of trapped volume was checked by comparative determinations of markers with established optical spectrophotometrical methods. The favorable results usingl atomic absorption spectrophotometry to quantitate the marker Mn2+ are of particular relevance as manganese ion is also the paramagnetic probe in n.m.r, measurements of water permeability of lipo-somes; our results indicate that in such measurements no other marker need be incorporated.. ...
Simple, accurate, sensitive and selective methods are described for the quantitative determination of ten fluoroquinolones (amifloxacin, ciprofloxacin hydrochloride, difloxacin hydrochloride, enoxacin, enrofloxacin, lomefloxacin hydrochloride, levofloxacin, norfloxacin, ofloxacin and pefloxacin mesylate). The methods are based on precipitation of the ion associates formed from the reaction of the cited drugs with silver nitrate, copper acetate and ferric chloride. The formation and solubility of the solid complexes at the optimum conditions of pH and ionic strength values have been studied. The methods depend on direct determination of the ions in the precipitate or indirect determination of the ions in the filtrate by atomic absorption spectroscopy. The optimum conditions for precipitation were carefully studied. Rectilinear calibration graphs were obtained in the range of 10-100 ng.ml-1 for each of the investigated drugs and the limits of detection and quantitation ranged from 1.125 to 2.260, o.937
en] A hydride generation flame atomic absorption spectrometric method was developed and optimized to quantitate arsenic (As) in foods. A wet digestion of the samples with HNO3 + H2O2 was performed and excess oxidants were eliminated by addition of hydrochloric acid and urea. As5+ in As3+ was then reduced by potassium iodide. The As3+ solution was analyzed by generation of arsine with sodium tetrahydroborate. As determination ranged from 2.5 to 20 microg/L, with a determination coefficient of 0.997. The limits of detection (LOD) and quantitation (LOQ) were 0.6 and 2.1 microg/L, respectively. The method was validated and good results were obtained for recovery, precision, accuracy, LOD, and LOQ. This method is now used to analyze foods from Rwanda ...
Over the past several years we have devised and expanded the capabilities of Zeeman atomic absorption spectroscopy (ZAA). Using this technique, trace elements in a complex matrix can be directly analyzed with high accuracy even when there is only one atom of interest contained in several million atoms of the host material. Quantities in the nanogram, or in some cases picogram, range can be determined within IS seconds for more than 30 elements. Because of its high selectivity and high sensitivity, ZAA can be used as a new technique for organometallic species determination by interfacing with a high pressure liquid chromatograph (HPLC). The HPLC separates various molecular species. Different kinds of mobil solvents can be directly introduced in the ZAA detection system; even organic solvents or high concentration salt solutions. Then, organometallic species in the ppb range are separately detected according to their retention times. This technique has a much larger field of application than HPLC coupled
Atomic Emission Spectroscopy AES Definition - Atomic emission spectroscopy (AES) is an analytical tool used to determine and quantify the elemental...
Watch this video to learn about Analytic Jenas ZEEnit series of graphite furnace atomic absorption spectrometers with Zeeman background correction. Discover how the features of the ZEEnit allow precise and reproducible results to be obtained immediately.
Determination of Pb (Lead), Cd (Cadmium), Cr (Chromium), Cu (Copper), and Ni (Nickel) in Chinese tea with high-resolution continuum source graphite furnace atomic absorption spectrometry ...
Optimization and validation of a methodology to determine total arsenic, As(III) and As(V), in water samples, through graphite furnace atomic absorption spectrometry ...
with little prisms and light bulbs etc.--see notes) 4.2 Atoms and Radiation: quantized energy levels of electrons in atoms, and how they interact with radiation. Exams are coming! Emission Spectroscopy: AAS. 1. The hydrogen atom--the simplest, and most important case. Intensity will look like a curve with many peaks. Nov 01, 2020 - Atomic Absorption Spectroscopy - PPT, Engg. Michigan State University. Get ready with unlimited notes and study guides! Header search input . This preview shows page 1 of the document.Unlock all 4 pages and 3 million more documents. Exam 27 October 2008, questions - Exam 3 Topic 1 Intro To Geotech - Foundation Chapter … OC883829. Atomic absorption is a special application in which ground-state atoms of metals absorb light at very specific wavelengths corresponding to the energy needed to cause electronic transitions in their electron orbitals. • Atomic emission spectroscopy (AES or OES) uses quantitative measurement of the optical emission from excited atoms to ...
Our objectives was to measure the serum zinc level in multidrug-resistant tuberculosis (MDRTB) patients and explore its association with different predictors of MDRTB in comparison with drug-sensitive tuberculosis (DSTB). We recruited 107 MDRTB and 87 DSTB patients from the National Institute of Diseases of the Chest and Hospital (NIDCH), Dhaka, in our study. We have used laboratory data on drug resistance patterns of these patients through the line probe assay. About 5 ml overnight fasting blood was collected from each patient to measure serum zinc level through the graphite furnace atomic absorption spectrophotometry method. Multivariate logistic regression in forward LR method was employed to measure the associated factors of MDRTB. Of them, serum zinc level was found significantly lower in MDRTB patients than DSTB (mean value, 65.1 µg/dl vs. 72.8 µg/dl, p-value|0.001). Younger age (Odds ratio [OR], 0.974; 95% confidence interval [CI], 0.951 - 0.997), female gender (OR, 3.480; 95% CI, 1.519-7.972
A biosorption procedure for separation-enrichment of aluminum in environmental samples has been presented in this work. Pseudomonas aeruginosa loaded on Chromosorb 106 has been used as biosorbent for that purpose. P. aeruginosa is a gram-negative, aerobic rod. The influences of pH of the aqueous solution, eluent type, eluent volume, sample volume, etc. were examined on the quantitative recovery of aluminum in R aeruginosa loaded on Chromosorb 106. The effects of concomitant ions on the recoveries of aluminum were also investigated. The detection limit based on 3 sigma for aluminum is 30 ng L(-1). Three certified reference materials (LGC 6010 Hard Drinking Water, NIST-SRM 1568a Rice Flour and NRCC-DORM-2 Dogfish Muscle) were analyzed for the validation of the presented procedure. The proposed procedure was applied to the determination of aluminum in environmental samples including natural water and food samples. The concentration of aluminum in real samples was found at ppb level. (C) 2007 ...
To ensure that the quality of metal plating is maintained at a high level, it is important to manage the concentration of metal ions in the plating solution. Flame atomic absorption spectroscopy and ICP emission spectroscopy can be used to quickly analyze metallic ions over a wide range of concentrations, from principal component to trace constituent levels. Here, using actual examples of analysis using the Shimadzu AA-7000 Atomic Absorption Spectrophotometer, we introduce factors to be considered in the analysis of metal ions in plating solution by flame atomic absorption. ...
Read independent reviews on Agilent 240FS AA Fast Sequential Atomic Absorption Spectrometer from Agilent Technologies on SelectScience
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Buck Scientific is an American manufacturer of atomic absorption spectrometers. Rugged - Compact - Reliable Instruments Made in America Since 1970
Atomic absorption spectrophotometry analyzes the concentration of elements in a liquid sample based on energy absorbed from certain wavelengths of light (usually 190 to 900 nm). ETAs, also called graphite furnaces, employ a small graphite tube whose temperature can be accurately controlled by a power supply (Figure 1). However, the efficiency of sample introduction is typically 5%, and the atoms are dispersed across a relatively large volume, causing the sensitivity of flame AAS to be relatively poor (typically parts per million level). E.H. Ivanova, in Encyclopedia of Analytical Science (Second Edition), 2005. A spectrophotometer is a complete system consists of a light source that gathers light that interacted with the subject and the spectrometer for measurement. Therefore, GF AAS is unsuitable for on-line hyphenations as chromatograms cannot be monitored with sufficient resolution. The hydrides are heated in the quartz tube to around 1000°C where they are atomized. The light source shines ...
A long-term study programme has evaluated heavy metals in the Bahía Blanca estuary, considering occurrence, concentration and distribution in the estuarine sediments, as well as their corresponding geochemical partitioning in the ,62 µm grain size fraction of the sediment. Total concentrations of heavy metals (Cd, Zn, Cu, Cr, Pb, Fe) have been determined through flameless atomic absorption spectrophotometry (AAS). Geochemical partitioning of these metals was determined following a sequential extraction technique. Furthermore, heavy metal distribution was studied against organic matter concentration within the sediments.. The results allow the characterization of the spatial distribution of the metals, together with their accumulation areas and potential sources. Bahía Blanca estuarine sediments have low to medium heavy metal concentrations. The geochemical partitioning indicated that many bioavailable species occur within the system, including those of highly toxic elements such as cadmium. ...
The importance of the rollover absorbance and the Zeeman sensitivity ratio related coefficient for the accuracy in the linearization of calibration curves in electrothermal atomic absorption spectrometry with Zeeman effect background correction ...
High quality graphite tubes manufactured compatible with Perkin Elmer, Shimadzu, Hitachi, Agilent, Thermo Scientific and GBC, suitable for Atomic Absorption Spectroscopy (AAS) instruments.
Equipment needed is very simple. These include excellent linear dynamic range and limit of detection, low chemical interference, multi-element capability as well as a stable, reproducible signal. The Atomic emission spectroscopy (AES) is a method of chemical analysis that uses the intensity of light emitted from a flame, plasma, arc, or spark at a particular wavelength to determine the quantity of an element in a sample. Compare the advantages and disadvantages of atomic absorption and inductively coupled plasma Atomic emission spectroscopy. Flame emission Spectroscopy The source of energy in Atomic Emission could be a flame like the one used in atomic absorption, or an inductively coupled plasma ( ICP ) . Complex mixture can be analysed either with or without their separation. AAS stands for Atomic Absorption Spectroscopy and AES stands Atomic Emission Spectroscopy.Both of these are spectro-analytical methods used in Chemistry in order to quantify the amount of a chemical species; in other ...
The standard for cadmium in rice based on JapansFood Sanitation Act has been strengthened, with theallowable concentration revised downward from1.0 mg/kg or less to a maximum of 0.4 mg/kgaccording to the Ministry of Health, Labour andWelfare Notification No. 183 (April 8, 2010). Therevised standard will take effect on February 28, 2011.Up to now, this type of restriction was applied only tobrown rice, but polished rice is now included in thisrevision.Here we introduce examples of analysis of cadmiumin standard reference materials of powdered brownrice (NIES No.10-a,-b) using the typical flame AAmethod, in addition to a high-sensitivity method usingan atom booster. ...
The mineral content was determined by atomic absorption spectrophotometry according to García and Báez () with a Varian atomic absorption spectrophotometer (AA .
To produce two comparable groups of patients, the characteristics are recorded using EURO-Score; additionally the groups are matched (Matched-Pairs-Analysis).. All patients are operated by the same surgeon (senior physician Dr. A.K. Menon) under general anaesthesia through median sternotomy with elective or urgent indications.. After induction of anaesthesia, within the first hour after admission to the Intensive Care Unit (ICU) and every further morning in the ICU or Intermediate Care Station (IMC), 10ml blood are removed by a central venous catheter, allowing to measure blood selenium levels in whole blood by electrothermal atomic absorption spectrometry.. All blood draws will be held on vascular access, which is lying independently of the study participation for surgery or for intensive care treatment. The blood samples will be stored until completion of the study and its evaluation (up to 24 months) and are discarded afterwards. All data collected are recorded on a documentation sheet. ...
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Levine, K., Stout, M., Ross, G., Essader, A., Perlmutter, J., Grohse, P., ... Collins, B. (2009). Validation of a method for the determination of chromium in rat feces by inductively coupled plasma optical emission spectrometry. Analytical Letters, 42(17), 2729 - 2746 ...
Sampling and analysis of nickel, ferronickel and nickel alloys. Method for determination of silver, arsenic, bismuth, cadmium, lead, antimony, selenium, tin, tellurium and thallium in nickel by electrothermal atomic absorption spectrometry ...
are the averages of the x and y measurements and S denotes summation over all n observations. When the points lie exactly on a straight line of positive slope R = +1; when the points lie exactly on a straight line of negative slope R = 1. Mathematically R lies between +1 and 1. Maybe this fact has given rise to the idea that R being near ± 1 indicates a linear relationship between the x and y variables. However values of R which can be considered large can come from markedly non-linear relationships.12,13 Although it has been discussed by many authors, in practice analysts misunderstand this concept. For analytical processes considering instrumental responses the calibration function is usually obtained by means of a calibration experiment; the observations usually represent the result of a physical measurement that must be converted into the analytical result.14 The model equation used is the straight line equation, Yi = b + aXi + ei (with i =1 to n), where Yi is the response variable, Xi the ...
Seven replicate measurements by cold vapour atomic absorption of a standard containing 1.00 ng/L of Hg, gave concentration determinations of 0.84, 1.50, 0.91,
atomic absorption 原子吸收;原子吸收作用 atomic absorption spectrometry 原子吸收光谱测定法 water absorption 吸水率;吸水性 moisture absorption 吸湿性;水分吸收 sound absorption 声吸收;吸音作用 absorption spectrum 吸收光谱;吸收频谱 absorption rate 吸收速率;吸收速度;分摊率 energy absorption 能量吸收 atomic absorption spectrophotometry [化]原子吸收分光光度法 absorption coefficient 吸收系数 absorption spectroscopy [光谱]吸收光谱学 infrared absorption 红外吸收;红外线吸收作用 shock absorption 减震;冲稽收;吸震作用 absorption tower 吸收塔 oil absorption [化]吸油量 atomic absorption spectrophotometer 原子吸收分光光度计 light absorption 光吸收 heat absorption [化]吸热;热吸收 ultraviolet absorption 紫外吸收;紫外线吸收;紫外光吸收 absorption system 吸收式系统 ...
Purchase your copy of BS ISO 17352:2008 as a PDF download or hard copy directly from the official BSI Shop. All BSI British Standards available online in electronic and print formats.
Candy sold in the market could be containing a heavy metals like copper. In this study, candy was destructed with HNO3, HNO3/H2SO4 (3:1) dan HNO3/H2SO4/H2O2 (6:2:1) to know the best matter oxidixer for copper. Then, evaluated the levels of copper using Atomic Absorption Spectrophotometer (AAS). The one way anove result with F test showed that the best oxidizer for copper in candy is HNO3/H2SO4. The average concentration of Copper in candy coded A, B, C, D, and E were 1. 72 mg/Kg; 1.69 mg/Kg; 1.57 mg/Kg; 1.71 mg/Kg; and 1.69 mg/Kg respectively. The content of copper in candies were the under daily dietary recommended limit based on SNI regulation. Key Words: Atomic Absorption Spectrophotometry, candy, matter oxidizer, time stability, wet destruction ...
Occupational exposure to beryllium may cause Chronic Beryllium Disease (CBD), a lung disorder initiated by an electrostatic interaction with the MHC class II human leukocyte antigen (HLA). Molecular studies have found a significant correlation between the electrostatic potential at the HLA-DP surface and disease susceptibility. CBD can therefore be treated by chelation therapy. In this work, we studied the effect of two complexing agents, nitrilotriproprionic acid (NTP) and 4,5-dihydroxy-1,3-benzene disulphonate (Tiron), on the fractionation of beryllium in human serum analysed by graphite furnace atomic absorption spectrometry (GFAAS). We found the average serum beryllium concentration of fourteen non-exposed individuals to be 0.53 (± 0.14) μg l-1, with 21 (± 3)% of the beryllium mass bound to the low molecular weight fraction (LMW), and 79 (± 3)% bound to the high molecular weight fraction (HMW). The addition of Tiron increased the beryllium mass in the HMW fraction, while NTP was not seen to have
建立了浸渍滤膜吸附-微波消解-原子荧光法测定环境空气中的砷的方法,改进了原有的采样方法,有效地克服了原方法中湿法消解的缺点,并大大降低了检出限,能够满足《环境空气质量标准》(GB 3095-2012)中对砷排放的参考浓度限值要求。;A new method was established to detect the arsenic in ambient air by using impregnated filter adsorption, microwave digestion and atomic fluorescence spectrometry, which improved the original sampling method and was more effective than the wet digestion. The method greatly reduced the detection limit to satisfy emission limit requirements in the national standard GB 3095-2012.
We offer a wide selection of CRMs to help the laboratory analyst achieve superior analytical results.Certified Reference Materials and Accreditation:Analytical measurements depend on many variables to provide the credible data needed to make informed decisions. The quality of this data is only as good as the reference material used to calibrate the measurement device. High quality reference materials are available only from organizations with a robust quality system. Accreditation to ISO/IEC 17025 and ISO Guide 34, also called Double Accreditation, represents the pinnacle of quality system achievement and allows the credible production and testing of Certified Reference Materials (CRMs).Note - Beginning June 15, 2015, customers will see a change in the accreditation symbols found on the Certificate of Analysis (COA) for Certified Reference Materials (CRMs)and Proficiency Testing samples (PTs) sold under Sigma-Aldrich US based CRM producers. The ACLASS accreditation
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An Inductively coupled plasma-atomic emission spectrometric method was developed for rapid screening of samples for the dithiocarbamate fungicide mancozeb. The method was based on determining the level of manganese, which forms a major part of the compound formulation, and was used to analyze urine, wash water, tank mixes, cellulose acetate...
Abstract Determination of Fe, Zn, Cu, K, P, Ca, Mg, Na, B and Al in cistanche and its extractives was carried out by the inductively coupled plasma atomic emission spectrometry (ICP-AES). The results showed that (1) the contents of Mn, K, Ca, Mg and Na in cistanche deserticola Y. C. Ma were 17.70, 16 278.03, 1 947.25, 1 662.76, and 106.79 respectively (μg·g-1), much higher than in Cistanche tubulosa (Schrenk) Wight; (2) the contents of Fe, Cu and P in 50% methanol extract of Cistanche deserticola were 1.5, 2.4, and 1.1 times that of aqueous extract respectively, the contents of Mn, Zn, K, P, Mg and Na were 3.8, 1.2, 1.6, 2.3, 2.2, and 1.1 times that of methanol extract respectively; (3) the contents of Cu and P in 50% methanol extract of Cistanche tubulosa were 1.6 and 1.2 times that of aqueous extract, the contents of Mn, Zn, K, P, Mg, Na and Al were 2.0, 1.6, 1.6, 1.4, 1.8, 1.2, and 1.2 times that of methanol extract respectively; (4) the leaching rate of 11 mineral elements in Cistanche ...
Twenty-one industrial, commercial and government laboratories participated in an interlaboratory measurement program using methods of their own choice.. Methods for the determination of the elements included digestion with various combinations of acids on a hot plate; and various types of fusions followed by the determination using inductively coupled plasma - atomic emission spectroscopy and inductively coupled plasma - mass spectrometry. Instrumental neutron activation analysis and X-ray fluorescence on a pressed powder pellet, fused pellet or after a fusion were used for many elements.. The concentration of carbon was determined using combustion followed by infrared spectrometry.. The concentration of sulphur was determined using combustion followed by infrared spectrometry; acid digestion using four acids or fusions followed by inductively coupled plasma - atomic emission spectroscopy, inductively coupled plasma - mass spectrometry or X-ray fluorescence.. ANOVA was used to calculate the ...
The results of a single-laboratory study of the SW-845 Method 7090/7091 -- Determination of Beryllium by Flame and Furnace Atomic Absorption Spectrophotometry are described. This study examined the application of these two powerful beryllium detection methods to the analysis of selected liquid and solid samples after digestion by appropriate SW-845 methods. method performance data including: detection limits, optimum concentration ranges (linearity), spike recoveries, interferences, precision, accuracy, and optimum instrument operating parameters, are presented and discussed ...
Sensitive speciation analysis of lead in environmental waters by capillary gas chromatography microwave-induced plasma atomic emission spectrometry ...
The objectives of this study were to determine background concentrations of metals and organic compounds in biotic and abiotic components of the Fort NiobraralValentine National Wildlife Refuge (NWR) Complex and document these results to utilize as baseline information for future contaminants investigations. To establish this baseline, sediment, water, and biotic samples (fish, double crested cormorant eggs, and vegetation) were collected from Fort Niobrara and Valentine National Wildlife Refuge in 1995 and tested for inorganic and organic contaminants. lnorganics were determined by inductively coupled plasma atomic emission spectrophotometer (lCP) scans. Arsenic and selenium were analyzed by atomic absorption spectrophotometry (AAS). Mercury levels were determined by cold vapor atomic absorption. Organochlorine scans were performed by capillary gas chromatography with an electron capture detector to determine organic contaminant levels. Elevated inorganic contaminant concentrations were detected in
OBJECTIVES--To study the effect of bis (tributyl tin) oxide (TBTO) on permeability of the blood-brain barrier. METHODS--Electron microscopy and an x ray microanalyser with lanthanum chloride as a tracer were used, and blood tin concentrations were determined with an atomic absorption spectrophotometer. Adult male wistar rats received 0.05 ml/kg body weight of TBTO orally. RESULTS--A transient increase in paracellular permeability at the blood-brain barrier was found 2 h after the dose of TBTO. Electron dense lanthanum deposits penetrated tight junctions of the endothelia and permeated the subendothelial space. The x ray microprobe data showed an accumulation of TBTO at the tight junctions at 2 h. Leakage of tracer did not occur at 4 h, but oedematous changes in the surrounding glial cells were prominent between 4 and 8 h and had almost returned to normal by 24 h. By atomic absorption analysis, it was seen that blood tin concentrations rapidly increased at 1 h and rose to a maximum peak at 8 h, ...
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In graduate school, Catherine worked on the implementation of Audio-Visual instruction for the optimization of the Atomic Absorption Spectrophotometer. She also worked on Caustic vs Acidic Digestion - Analyzing Fe-impregnated Zeolite X using Atomic Absorption Spectrophotometry. ...
We specialize in certified reference materials as well as certified reference standards, chemical reference standards and analytical reference standards. We also specialize in analytical reference materials as well as pharmaceutical reference standards, environmental reference standards and forensic reference standards. Please visit our website for more details.
We specialize in certified reference materials as well as certified reference standards, chemical reference standards and analytical reference standards. We also specialize in analytical reference materials as well as pharmaceutical reference standards, environmental reference standards and forensic reference standards. Please visit our website for more details.
Many employees in the aluminum industry are exposed to a range of aluminum compounds by inhalation, and the presence of ultrafine particles in the workplace has become a concern to occupational health professionals. Some metal salts and metal oxides have been shown to enter the brain through the olfactory route, bypassing the blood-brain barrier, but few studies have examined whether aluminum compounds also use this pathway. In this context, we sought to determine whether aluminum was found in rat olfactory bulbs and whether its transfer depended on physicochemical characteristics such as solubility and granulometry. Aluminum salts (chloride and fluoride) and various nanometric aluminum oxides (13nm, 20nm and 40-50nm) were administered to rats by intranasal instillation through one nostril (10?g Al/30?L for 10days). Olfactory bulbs (ipsilateral and contralateral relative to instilled nostril) were harvested and the aluminum content was determined by graphite furnace atomic absorption ...
Design and performance of a tunable diode laser absorption spectrometer for airborne formaldehyde measurements Journal Article ...
In the last few decades, wheat-based products have received considerable attention in view of their potential role in transporting of microelements into the human diet. In Yemen, bread is the staple food, produced in different kinds from local and imported wheat. Most of it is not subjected to microelemental analysis. The objective of this study is to determine quantitatively the microelement such as Fe, Cu, Mn, Zn, Co, Cd and Pb in samples of wheat grains produced locally from different cultivated regions in Yemen as well as those imported from USA and Austria. Flame atomic absorption spectrophotometry was used for analysis. The results show that the contents of the microelements in the studied samples are generally within the permissible levels except cadmium. The samples collected from middle altitude and eastern plateau the cadmium is above the permissible level.
0041]FIG. 3A shows the evolution of current-versus-voltage (I-V) characteristic of the MOS structure over repeated application of a pulse (100 V amplitude and 10 ms width): after each pulse drive the I-V characteristic was measured for V of 0 to 10 V. A fresh sample (before pulse drive) shows tunneling-limited current at ˜10-10 A, which corresponds to a nominal current density (normalized by the electrode area) of ˜10-8 A/cm2. The current jumps up to the 10-5 A level after the first pulse, and then to the 10-4 A level after the second pulse, all read at 10 V. It finally settles at around the 10-3 A level after the fifth pulse. Without implicating a particular theory, the inventors note that this dramatic increase can be attributed to formation of localized leakage paths in the oxide. If ˜3 nm-diameter leakage channels is assumed, with an area density of 1×106 cm-2, then the measured injection current (0.5 A at 100 V: FIG. 2B) translates into a current density of ˜1×109 A/cm2 in the ...
Sample collection for oxaliplatin and FU pharmacokinetics. Heparinized 7-mL blood samples were collected for determination of platinum in plasma ultrafiltrate and plasma FU concentrations at 0 (predose), 1, 2 (end of oxaliplatin infusion, start of FU bolus), 2.25, 2.5, 3, 4, 6, 8, and 24, and between 44 and 48 h, with the average of the last three samples (8, 24, and 46 h) being used to determine the steady-state FU concentration.. Platinum measurements. Plasma ultrafiltrate was prepared from plasma by centrifugal ultrafiltration using Amicon Centrifree Micropartition Systems (Millipore Corporation), and platinum was measured with a validated flameless atomic absorption spectrophotometric (PE ZL4100, Perkin Elmer) method (33). Briefly, plasma ultrafiltrate was diluted 1:1 in 0.1% nitric acid + 0.2% Triton X-100, and a 20 μL was injected into the atomic absorption spectrophotometer. Platinum standards were prepared in the same manner and in the same matrix. Quality assurance was maintained by ...
The formation, atomic and chemical composition, evolution and fate of molecular gas clouds is of special interest, because it ... Advances in Standards and Methodology in Spectrophotometry. Burlington: Elsevier Science. p. 1. ISBN 978-0444599056. "A ... If the hydrogen is atomic, then the H atoms react with available O, C and N atoms, producing "reduced" species like H2O, CH4, ... as the theory allowed for these results to be compared to atomic and molecular emission spectra which had been calculated a ...
"Cinchocaine hydrochloride determination by atomic absorption spectrometry and spectrophotometry". Farmaco. 60 (5): 419-24. doi: ...
In a separate sample, Beryllium was 84.93 mg by atomic absorption spectrophotometry. To determine water an H analyzer was used ... In X-ray scattering and diffraction models the data presents an approximation of the number of electrons in each atomic site, ...
This makes it possible also to study the isotopic composition of a sample with infrared spectrophotometry. Atomic absorption ... Spectrophotometry in infrared light is mainly used to study structure of substances, as given groups give absorption at defined ... Metals in the solution are present in atomic form in the flame. The monochromatic light in this type of photometer is generated ...
He credited the Corona Lab program with the establishment of the atomic wavelength standard in the infrared. Humphreys attended ... His inventions significantly advanced the techniques of radiometry and spectrophotometry. ... Standards 1953, 50, 1. "Interferometric measurement of wavelengths of infrared atomic emission lines in the extraphotographic ... which at the time was the most distinguished group of spectroscopic and atomic physicists ever assembled, and included the ...
... content of samples is determined by atomic absorption spectrophotometry or by potentiometry using ion-selective ... Due to having low atomic mass and large atomic radius, sodium is third-least dense of all elemental metals and is one of only ... Atomic sodium has a very strong spectral line in the yellow-orange part of the spectrum (the same line as is used in sodium ... In stars, it is seen in any whose surfaces are cool enough for sodium to exist in atomic form (rather than ionised). This ...
MDP with synthetic hydroxyapatite was observed using x-ray photoelectron spectroscopy and atomic absorption spectrophotometry. ...
Analytical methods for the determination of lead in the environment include spectrophotometry, X-ray fluorescence, atomic ... despite its relatively high atomic number, is more prevalent than most other elements with atomic numbers greater than 40. ... Lead's high density, atomic number, and formability form the basis for use of lead as a barrier that absorbs sound, vibration, ... With its high atomic number, lead is the heaviest element whose natural isotopes are regarded as stable; lead-208 is the ...
The NIFA administers cobalt-60 radiation source, Laser absorption spectrometer and Atomic Absorption Spectrophotometry, Near- ... NIFA was the brainchild of Ishrat Hussain Usmani, bureaucrat and chairman of the Pakistan Atomic Energy Commission, however due ... is one of four agriculture and food irradiation research institute managed by the Pakistan Atomic Energy Commission. The ...
"Estimation of zinc concentration of parotid saliva by flameless atomic absorption spectrophotometry in normal subjects and in ...
Atomic Absorption Spectrophotometry (AAS) and Inductively Coupled Plasma Mass Spectrometry (ICP-MS) are used to detect ...
... atomic absorption spectrophotometry, inductively coupled plasma spectrometry, ion chromatography, and colorimetric methods. In ... Blaylock, Michael J.; James, Bruce R. (1993). "Selenite and selenate quantification by hydride generation-atomic absorption ...
... while the calcium and magnesium ion concentrations can be determined by atomic absorption spectrophotometry. Dissolved load can ...
Tyson, Julian F. (1985). "Flow injection analysis techniques for atomic-absorption spectrometry. a review". The Analyst. 110 (5 ... Over past 30 years, FIA techniques developed into a wide array of applications using spectrophotometry, fluorescence ... spectroscopy, atomic absorption spectroscopy, mass spectrometry, and other methods of instrumental analysis for detection. ...
... and Graphite Furnace Atomic Absorption Spectrometry D6358 - 19e1 Classification System and Basis for Specification for Poly ( ... e1 Test Method for Vinyl and Trans Unsaturation in Polyethylene by Infrared Spectrophotometry D6249 - 19 Guide for Alkaline ... 14 Test Methods for Total Mercury in Coal and Coal Combustion Residues by Acid Extraction or Wet Oxidation/Cold Vapor Atomic ... Test Method for Zinc Analysis of Floor Polishes and Floor Polish Polymers By Flame Atomic Absorption (A.A.) D6828 - 02(2019) ...
... and Soil by Flame Atomic Absorption Spectrophotometry (FAAS) E3195 - 19 Guide for Body Armor Program Management E3197 - 20 ... Flame Atomic Absorption Spectrometry (FAAS), or Graphite Furnace Atomic Absorption Spectrometry (GFAAS) Techniques E1614 - 94( ... 16 Test Method for Analysis of Titanium and Titanium Alloys by Spark Atomic Emission Spectrometry and Glow Discharge Atomic ... 19 Test Method for Determination of Low Levels of Antimony in Carbon and Low-Alloy Steel by Graphite Furnace Atomic Absorption ...
... spectrophotometry, atomic MeSH E05.196.712.726.676 - spectrophotometry, infrared MeSH E05.196.712.726.676.700 - spectroscopy, ... spectrophotometry, atomic MeSH E05.196.867.826.676 - spectrophotometry, infrared MeSH E05.196.867.826.676.700 - spectroscopy, ... atomic force MeSH E05.595.666.500 - microscopy, scanning tunneling MeSH E05.598.500.249 - arthritis, experimental MeSH E05.598. ... spectrophotometry MeSH E05.196.712.726.300 - microspectrophotometry MeSH E05.196.712.726.551 - ...
... and Sodium in Atmospheric Wet Deposition by Flame Atomic Absorption Spectrophotometry D5087 - 02(2014) Test Method for ... Inductively Coupled Plasma Atomic Emission Spectrometry, and Atomic Absorption Spectrometrye espectrometria de absorção ... Atomic Emission Spectrometry D5709 - 09(2015) Test Method for Sieve Analysis of Petroleum Coke D5710/D5710M - 15 Specification ... by Infrared Spectrophotometry D5671 - 20 Practice for Polishing and Etching Coal Samples for Microscopical Analysis by ...
... spectrophotometry. Both the UK Health and Safety Laboratory and NIOSH Manual of Analytical Methods have specific methodologies ... filter and acid digestion of the collection media in the laboratory followed by measuring metal concentration though an atomic ...
... and Brines by Atomic Absorption Spectrophotometry D3562 - 14 Performance Specification for Woven Drycleanable Coat Fabrics ... 13 Test Method for Dissolved Copper In Electrical Insulating Oil By Atomic Absorption Spectrophotometry D3636 - 19 Practice for ... 15 Practice for Measuring Trace Elements in Water by Graphite Furnace Atomic Absorption Spectrophotometry D3920 - 18 Test ... 16 Practices for Digestion of Water Samples for Determination of Metals by Flame Atomic Absorption, Graphite Furnace Atomic ...
15 Test Method for Sodium in Water by Atomic Absorption Spectrophotometry D4192 - 15 Test Method for Potassium in Water by ... Atomic Absorption Spectrophotometry, Graphite Furnace D4383 - 18 Specification for Plowable, Raised Retroreflective Pavement ... Test Method for Metals in Cellulose by Atomic Absorption Spectrophotometry D4086 - 18 Practice for Visual Evaluation of ... 17 Test Method for Measurement of Metals in Workplace Atmospheres by Flame Atomic Absorption Spectrophotometry D4186/D4186M - ...
Metals are commonly measured by atomic spectroscopy and mass spectrometry: Atomic Absorption Spectrophotometry (AAS) and ... Inductively Coupled Plasma Atomic Emission (ICP-AES) or Inductively Coupled Plasma Mass Spectrometric (ICP-MS) techniques. ...
Spectrophotometry - measurement of the transmission of light through different solutions or substances at different wavelengths ... Atomic force microscopy - Neuroimaging - Neutron spin echo spectroscopy - Nuclear Magnetic Resonance Spectroscopy - method for ... Biophysical techniques - methods used for gaining information about biological systems on an atomic or molecular level. They ... method to determine the exact structure of molecules with atomic resolution Biophysical profile Molecular biophysics Biological ...
Atomic absorption spectrophotometry Atomic emission spectroscopy Inductively coupled plasma atomic emission spectroscopy ... Spectrophotometry is also a helpful process for protein purification and can also be used as a method to create optical assays ... Spectrophotometry is a tool that hinges on the quantitative analysis of molecules depending on how much light is absorbed by ... Samples for IR spectrophotometry may be smeared between two discs of potassium bromide or ground with potassium bromide and ...
"Standard Practice for Measuring Trace Elements in Water by Graphite Furnace Atomic Absorption Spectrophotometry." ASTM D6357-11 ... Graphite furnace atomic absorption spectroscopy (GFAAS) (also known as Electrothermal Atomic absorption spectroscopy (ETAAS)) ... Graphite Furnace Atomic Absorption Spectrometry." EPA Analytic Technology Encyclopedia Research Group of Atomic Spectrometry ... GFAAs are more sensitive than flame atomic absorption spectrometers, and have a smaller dynamic range. This makes it necessary ...
atomic mass unit See unified atomic mass unit. atomic number (Z) The number of protons found in the nucleus of an atom of a ... This type of absorption is the principle on which spectrophotometry is based. abundance accuracy How close a measured value is ... atomic radius atomic weight average atomic mass Avogadro's law Avogadro's number The number of discrete constituent particles ( ... atomic mass The mass of an atom, typically expressed in unified atomic mass units and nearly equivalent to the mass number. ...
Atomic Ratio of Nuclear Grade Uranium Dioxide Powders and Pellets C1455 - 14e1 Test Method for Nondestructive Assay of Special ... Diode Array Spectrophotometry C1308 - 08(2017) Test Method for Accelerated Leach Test for Diffusive Releases from Solidified ... and Atomic Absorption (AA) C1303/C1303M - 19 Test Method for Predicting Long-Term Thermal Resistance of Closed-Cell Foam ... Test Method for Major and Trace Elements in Limestone and Lime by Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP ...
In fact, gravimetric analysis was used to determine the atomic masses of many elements to six figure accuracy. Gravimetry ... Compare this with hardy methods such as spectrophotometry and one will find that analysis by these methods is much more ...
Electrons are excited from their current molecular/atomic orbital. Once excited an electron can either dissipate the energy as ... Spectrophotometry. *Theory of solar cells. *Thermophotovoltaics. References[edit]. *^ a b Solar Cells. chemistryexplained.com ...
Metals are commonly measured by atomic spectroscopy and mass spectrometry: Atomic Absorption Spectrophotometry (AAS) and ... Inductively Coupled Plasma Atomic Emission (ICP-AES) or Inductively Coupled Plasma Mass Spectrometric (ICP-MS) techniques. ...
Cold vapour atomic fluorescence spectroscopy. *Conversion electron mössbauer spectroscopy. *Correlation spectroscopy. *Deep- ... Spectrophotometry. *Time-resolved spectroscopy. *Time-Stretch. *Thermal infrared spectroscopy. *Video spectroscopy. * ...
This material is mostly composed of ionized and atomic sulfur, oxygen and chlorine; atomic sodium and potassium; molecular ... 1980). "Spectrophotometry of Io: Preliminary Voyager 1 results". Geophys. Res. Lett. 7 (11): 963-966. Bibcode:1980GeoRL...7.. ... 2), with minor constituents including sulfur monoxide (SO), sodium chloride (NaCl), and atomic sulfur and oxygen.[106] The ...
Tennyson, Jonathan (2005). Astronomical spectroscopy : an introduction to the atomic and molecular physics of astronomical ... Oke, J. B.; Gunn, J. E. (1983). "Secondary standard stars for absolute spectrophotometry". The Astrophysical Journal. 266: 713 ... Nahar, Anil K. Pradhan, Sultana N. (2010). Atomic astrophysics and spectroscopy. Cambridge: Cambridge University Press. pp. 7, ... and spectrophotometry". Icarus. 25 (1): 104-130. Bibcode:1975Icar...25..104C. doi:10.1016/0019-1035(75)90191-8.. ...
Oke, J. B.; Gunn, J. E. Secondary standard stars for absolute spectrophotometry. The Astrophysical Journal. 1983, 266: 713. ... 原子和分子天體物理學(英语:Atomic and molecular astrophysics) ... Nahar, Anil K. Pradhan, Sultana N. Atomic astrophysics and spectroscopy. Cambridge: Cambridge University Press. 2010: 7,221. ... Surface properties of asteroids: A synthesis of polarimetry, radiometry, and spectrophotometry. Icarus. May 1975, 25 (1): 104- ...
... is a spectroscopic technique to observe local magnetic fields around atomic nuclei. The sample is placed in a magnetic field ... and at the same time not by other spectroscopic techniques to an atomic level, either. In solid-phase media, such as crystals, ... Spectrophotometry. *Time-resolved spectroscopy. *Time-stretch. *Thermal infrared spectroscopy. *Video spectroscopy. * ...
2016). "Atomic weights of the elements 2013 (IUPAC Technical Report)". Pure and Applied Chemistry. 88 (3): 265-91. doi:10.1515/ ... The element is used as an internal standard in spectrophotometry.[83] Like other alkali metals, caesium has a great affinity ... Caesium-based atomic clocks use the electromagnetic transitions in the hyperfine structure of caesium-133 atoms as a reference ... Standard atomic weight. .mw-parser-output .nobold{font-weight:normal}. Ar, std(Cs). 132.90545196(6)[1]. ...
Scattering cross sections may be defined in nuclear, atomic, and particle physics for collisions of accelerated beams of one ... "2. Spectrophotometry". Biological Instrumentation and Biology. ISBN 978-81-219-2633-1. ... Cross sections can be computed for atomic collisions but also are used in the subatomic realm. For example, in nuclear physics ... Differential and total scattering cross sections are among the most important measurable quantities in nuclear, atomic, and ...
1980). "Spectrophotometry of Io: Preliminary Voyager 1 results". Geophys. Res. Lett. 7 (11): 963-966. Bibcode:1980GeoRL...7.. ... sodium dan potassium atomic; sulfur dioksida dan sulfur molekuler; dan debu sodium klorida.[53][54] Materi-materi tersebut ...
... the atomic polar tensor (APT). This contrasting feature allows rovibronic transitions that might not be active in IR to be ... Spectrophotometry. *Time-resolved spectroscopy. *Time-stretch. *Thermal infrared spectroscopy. *Video spectroscopy. * ...
... (IUPAC spelling[6]) or cesium (American spelling)[note 1] is a chemical element with symbol Cs and atomic number 55. It ... The element is used as an internal standard in spectrophotometry.[84] Like other alkali metals, caesium has a great affinity ... Caesium-based atomic clocks use the electromagnetic transitions in the hyperfine structure of caesium-133 atoms as a reference ... Essen, L.; Parry, J. V. L. (1955). "An Atomic Standard of Frequency and Time Interval: A Caesium Resonator". Nature. 176 (4476 ...
Chemical analysis by spectrophotometryEdit. Beer-Lambert law can be applied to the analysis of a mixture by spectrophotometry, ... Atomic absorption spectroscopy. *Absorption spectroscopy. *Cavity ring-down spectroscopy. *Infra-red spectroscopy ... with solute is ratioed against the transmittance of the pure solvent which explains why it works so well in spectrophotometry. ...
Working with the Red Army Engineering Unit, she developed a method of spectrophotometry to be used in the field which dealt ... She continued teaching first chemistry, then courses on atomic matter, radioactivity and pedagogy until 1919 at Second ...
1913 Niels Bohr introduces concepts of quantum mechanics to atomic structure by proposing what is now known as the Bohr model ... it establishes the analytical technique known as spectrophotometry. 1855 Benjamin Silliman, Jr. pioneers methods of petroleum ... 1924 Louis de Broglie introduces the wave-model of atomic structure, based on the ideas of wave-particle duality. 1925 Wolfgang ... 1913 Henry Moseley, working from Van den Broek's earlier idea, introduces concept of atomic number to fix inadequacies of ...
... is a coefficient used in spectrophotometry to estimate selectivity (amount of overlapping of spectra) in a quantitative ... figures of merit estimation for determination of trace elements in geological materials by inductively coupled plasma atomic ...
Atomic spectroscopy was the first application of spectroscopy developed. Atomic absorption spectroscopy and atomic emission ... Raman spectroscopy Saturated spectroscopy Scanning tunneling spectroscopy Spectrophotometry Spin noise spectroscopy traces ... Atomic absorption lines are observed in the solar spectrum and referred to as Fraunhofer lines after their discoverer. A ... These absorptions and emissions, often referred to as atomic spectral lines, are due to electronic transitions of outer shell ...
Most of the elements were discovered and named in the West, as well as the contemporary atomic theories to explain them.[ ... Other important diagnostic tools of clinical chemistry, including the methods of spectrophotometry, electrophoresis and ... Nuclear power stations are derived from the first atomic pile constructed in Chicago in 1942. Communication devices and systems ... Oak Ridge, Tennessee: United States Atomic Energy Commission, Division of Technical Information. pp. 22-26. Coe, Lewis (1995). ...
This material is mostly composed of ionized and atomic sulfur, oxygen and chlorine; atomic sodium and potassium; molecular ... 1980). "Spectrophotometry of Io: Preliminary Voyager 1 results". Geophys. Res. Lett. 7 (11): 963-966. Bibcode:1980GeoRL...7.. ... by atomic ratio) of any known astronomical object in the Solar System. It was discovered in 1610 by Galileo Galilei and was ... and atomic sulfur and oxygen. The atmosphere has significant variations in density and temperature with time of day, latitude, ...
Spectrophotometry is a technique used in measuring the quantity ... ... The basic principle of atomic absorption spectrophotometry states that atoms absorb specific wavelengths of electromagnetic ... Spectrophotometry is a useful tool in quantitative analysis where the concentration of a substance is to be identified. Atomic ... What does Daltons atomic theory state?. A: Daltons atomic theory states four critical truths about atoms: firstly, everything ...
D4691-17 Standard Practice for Measuring Elements in Water by Flame Atomic Absorption Spectrophotometry flame atomic absorption ... 5.2 The major advantage of atomic absorption over atomic emission is the almost total lack of spectral interferences. In atomic ... Flame atomic absorption spectrophotometry is simple, rapid, and applicable to a large number of elements in drinking water, ... Standard Practice for Measuring Elements in Water by Flame Atomic Absorption Spectrophotometry. Active Standard ASTM D4691 , ...
Standard Test Method for Metals in Cellulose by Atomic Absorption Spectrophotometry calcium content~ iron content~ metal ... Standard Test Method for Metals in Cellulose by Atomic Absorption Spectrophotometry. Active Standard ASTM D4085 , Developed by ... ASTM D4085-93(2013), Standard Test Method for Metals in Cellulose by Atomic Absorption Spectrophotometry, ASTM International, ...
Magnesium in Waters and Sewage Effluents by Atomic Absorption Spectrophotometry by Great Britain, 9780117513129, available at ...
Measurement of Chromium in Soil by Atomic Absorption Spectrophotometry This Application News introduces an example of chromium ... Elemental Analysis, Atomic Absorption Spectroscopy. Keywords:. Environment, Soil, Fertilizer, Waste Material Test. Language:. ...
Comparison of the determination of magnesium by methylthymol blue spectrophotometry and atomic absorption spectrophotometry.. [ ... of 30 patients on an intensive ward were analysed for magnesium simultaneously by atomic absorption spectrophotometry (AAS) and ... Methylthymol blue spectrophotometry was performed at the bedside, using two different multianalysers, Easy ST 1 and Easy ST 2, ... Comparison of AAS and methylthymol blue spectrophotometery showed that methylthymol blue spectrophotometry produced higher ...
Iraq by flame atomic absorption spectrophotometry. The crude oils are characterized with API gravity values in the range, 25 - ... Iraq by flame atomic absorption spectrophotometry. The crude oils are characterized with API gravity values in the range, 25 - ... Sebor, G., Lang, I., Vavrecka, P., Sychra, V. and Weisser, O. (1975) The Determination of Metals in Petroleum Samples by Atomic ... of Analytical Procedures in the Determination of Trace Metals in Heavy Crude Oils by Flame Atomic Absorption Spectrophotometry ...
Standard Test Method for Sodium in Water by Atomic Absorption Spectrophotometry Status : Current Published : January 2015 ... ASTM D4085 - 93(2013) Standard Test Method for Metals in Cellulose by Atomic Absorption Spectrophotometry ... ASTM D4192 - 15 Standard Test Method for Potassium in Water by Atomic Absorption Spectrophotometry ... and Sodium in Atmospheric Wet Deposition by Flame Atomic Absorption Spectrophotometry * ...
... by Atomic Absorption Spectrophotometry Nabila S. Zaki, Mahmood M. Barbooti, Sulafa S. Baha-Uddin, and Eman B. Hassan ... in four heavy distillates from three heavy crude oils and one commercial crude oil by atomic absorption spectrophotometry. The ...
... and nickel in the samples were determined using atomic absorption spectrophotometry. (Author)(*SEA WATER ... and nickel in the samples were determined using atomic absorption spectrophotometry. (Author) ... Title : An Analysis of the Concentrations of Heavy Metals in Monterey Harbor Utilizing the Methods of Atomic Absorption ... Descriptors : (*SEA WATER, METALS), ATOMIC SPECTROSCOPY, POLAROGRAPHIC ANALYSIS, COBALT, IRON, COPPER, LEAD(METAL), NICKEL, ...
... , Paul Ocheje ... Analysis of some trace metals in human hair using atomic absorption spectrophotometry for forensic applications. Paul Ocheje ... Analysis of some trace metals in human hair using atomic absorption spectrophotometry for forensic applications. J Ind Environ ... Among others, atomic fluorescence spectrometry inductively coupled plasma atomic emission spectrometry (ICP-AES) ...
Comparison of liposome entrapment parameters by optical and atomic absorption spectrophotometry. Norma L. Yoss, Octavian ... Comparison of liposome entrapment parameters by optical and atomic absorption spectrophotometry. Norma L. Yoss, Octavian ... The validity of atomic absorption spectrophotometry Ior measuring markers of trapped volume was checked by comparative ... Comparison of liposome entrapment parameters by optical and atomic absorption spectrophotometry Message Subject (Your Name) has ...
Atomic Absorption Spectrophotometry.. Platinum was measured by using a Perkin-Elmer atomic absorption spectrometer (AAnalyst ... and platinum content by atomic absorption spectrophotometry. The platinum reading was normalized to protein concentration. ... The amount of platinum in whole cells was measured using the atomic absorption spectrophotometer after incubating cells with 1 ... Platinum was measured using an atomic absorption spectrometer. Numbers represent absorption by atomized platinum divided by A ...
Atomic absorption spectroscopy (AAS) is similar to flame photometry with the difference that it measures the absorption of a ... Atomizer: The elements which needs to be analysed needs to be in the atomic state. Here comes the role of atomizer. It breaks ... The major difference in the instrumentation of AAS and flame spectrophotometry is the presence of a radiation source (a ... transduction pathway signaling signaling molecules smooth ER sowing Spectrofluorimetry Spectrophotometer Spectrophotometry ...
Tagged AAS, and, atomic abosrption spectrophotometry, Chemistry, experiment, first year chemistry, general chemistry, iron, ... Analysis of Iron by Atomic Absorption Spectrophotometry. Posted on September 12, 2019. by Lawrence Graves ... Analysis of iron by atomic absorption spectrophotometry In this experiment, the iron content in a. childrens multivitamin will ... be analyzed using atomic absorption spectrophotometry. (AAS), and compared to the quantity stated on the package label. The ...
... offering services and Solutions of Atomic Absorption Spectrophotometry - AAS based In Ghatkopar(W), Mumbai, Maharashtra, India ... Atomic Absorption Spectrophotometry (AAS). P { margin-bottom: 0.08in; }. Fe, Co, Ni, Cu, Zn, Cr, Cd, Pb, Al, Mn, Na, K, Ca, Mg ...
Good quality atomic absorption spectrophotometry from atomic absorption spectrophotometry manufacturer, Buy atomic absorption ... High Precision Automatic Graphite Furnace Atomic Absorption Spectroscopy / Agriculture detection Contact Now ... Atmosphere Life sciences Graphite Furnace Atomic Absorption Spectroscopy Titanium burner Contact Now ... Eight Lamp Graphite Furnace And Flame Automatic Atomic Absorption Spectrophotometer Contact Now ...
The Scientific & Educational Acronym /Abbreviation/Slang AAS means Atomic Absorption Spectrophotometry. by AcronymAndSlang.com ... AAS stands for "Atomic Absorption Spectrophotometry". Q: A: How to abbreviate "Atomic Absorption Spectrophotometry"?. "Atomic ... Atomic Absorption Spectrophotometry can be abbreviated as AAS. AAS - Atomic Absorption Spectrophotometry in Scientific & ... AAS as abbreviation means "Atomic Absorption Spectrophotometry". Q: A: What is shorthand of Atomic Absorption Spectrophotometry ...
2.3.4. Atomic absorption spectroscopic studies. The actual amount of metal content present in the synthesised catalysts (M/TiO2 ... 2.3.5. UV-visible spectrophotometry. UV-visible spectra of all the samples were recorded using UV-Vis double beam ... 3.1.2. Atomic absorption spectrophotometric analysis. To determine the actual metal content of all the synthesised M/TiO2 ... 3.1.1. UV-visible spectrophotometry. The absorption spectra of synthesised TiO2 (gel form) was recorded using UV-visible ...
Rao, P.D., 1972, The determination of titanium in titaniferous magnetite ores by atomic absorption spectrophotometry: ... The determination of titanium in titaniferous magnetite ores by atomic absorption spectrophotometry. ... In attempting to analyze lithium metaborate fusions (7, 8) of titaniferous magnetite ores of Alaska by atomic absorption, it ... have investigated titanium by atomic absorption and have recommended a number of different procedures to remove interference. ...
The mineral content was determined by atomic absorption spectrophotometry according to García and Báez () with a Varian atomic ... Analytical Methods for Atomic Absorption Spectrophotometry Analytical Methods for Atomic Absorption Spectrophotometry, ... Atomic-Absorption Spectrophotometry focuses on the use of atomic absorption spectrophotometry as an analytical technique. ... atomic emission spectrophotometry and atomic absorption spectrophotometry and much more.. It can also be classified into two ...
... in beer by atomic absorption spectrophotometry Descriptors example of the calibration of the level of zinc obtained by atomic ... Zinc in Beer by Atomic Absorption Spectrophotometry (IM) - The determination of zinc ... The determination of zinc in beer by atomic absorption spectrophotometry. Descriptors: example of the calibration of the level ... 9.20 - Zinc in Beer by Atomic Absorption Spectrophotometry (IM). * 23/10/2018 ...
"Fully Automatic Double Beam - Atomic Absorption Spectrophotometer (AA 8000)". Laboratory Equipment. Labindia Analytical ... "Spectrophotometry". NIST. Retrieved Dec 23, 2018.. *^ a b c d e f g h i j Ninfa AJ, Ballou DP, Benore M (2010). Fundamental ... UV-visible spectrophotometry[edit]. Main article: Ultraviolet-visible spectroscopy. Most spectrophotometers are used in the UV ... "Spectrophotometry Applications and Fundamentals". www.mt.com. Mettler-Toledo International Inc. Retrieved Jul 4, 2018.. ...
Spector H, Glusman S, Jatlow P, Seligson D. Direct determination of copper in urine by atomic absorption spectrophotometry. ... Direct determination of copper in urine by atomic absorption spectrophotometry. In: Clinica Chimica Acta. 1971 ; Vol. 31, No. 1 ... Fingerprint Dive into the research topics of Direct determination of copper in urine by atomic absorption spectrophotometry. ... title = "Direct determination of copper in urine by atomic absorption spectrophotometry",. abstract = "A method is studied for ...
Comparison study between colorimetric method and flame atomic absorption spectrophotometry in serum zinc status ... Objectives: This paper presents a comparison study of Flame Atomic Absorption Spectrometry (FASS) and the Colorimetric method ...
Keywords: Spectrophotometry ,Methods Subjects: Antihypertensive Agents , Analysis *Abstract English. Atomic absorption ... Atomic absorption spectrophotometry for the determination of some antihypertensive agents Egypt. J. Pharm. Sci. 1994; 35 (6-Jan ... Citation: M. Y. Ebeid , Atomic absorption spectrophotometry for the determination of some antihypertensive agents, Egypt. J. ... The excess barium chloride in the decanted solution was determined by atomic absorption spectrophotometry ...
Select 2018 high quality Atomic Absorption products in best price from certified Chinese Laboratory Equipments manufacturers, ... Water Chiller for Atomic Absorption Spectrophotometry Industrial Chiller FOB Price: US $ 650-15000 / Piece. Min. Order: 1 Piece ... Atomic Absorption Analysis Atomic Absorption Analyzer Atomic Absorption Spectroscopy Atomic Absorption Factory Wholesale Atomic ... Atomic Absorption Spectrophotometer Atomic Absorption Spectrometer Air Mercury Analyzer Atomic Absorption Aas Atomic Absorption ...
This solution, or a dilution thereof, is analyzed for sodium and potassium content by atomic absorption spectrophotometry. ...
Journal > ALCHEMY > Analysis of Metal Copper Concentration at Candy using Atomic Absorption Spectrophotometry (AAS) ... Analysis of Metal Copper Concentration at Candy using Atomic Absorption Spectrophotometry (AAS) ... Atomic Absorption Spectrophotometry, candy, matter oxidizer, time stability, wet destruction ... Then, evaluated the levels of copper using Atomic Absorption Spectrophotometer (AAS). The one way anove result with F test ...
  • Among others, atomic fluorescence spectrometry inductively coupled plasma atomic emission spectrometry (ICP-AES) spectrofluorimetric and differential pulse anodic stripping voltammetry (DPASV), Particle - induced X-ray emission (PIXE), Energy dispersive spectrum (EDS), energy dispersive X-Ray fluorescence, (EDXFA), Electro Thermal Atomic Absorption Spectroscopy (ETAAS), neutron activation analysis (NAA), microscopy and DNA analysis have been used widely used for forensic hair analysis [ 2 , 3 - 15 ]. (alliedacademies.org)
  • Atomic absorption spectroscopy (AAS) is similar to flame photometry with the difference that it measures the absorption of a beam of monochromatic light by the atoms in the flame. (blogspot.in)
  • Atmosphere Life sciences Graphite Furnace Atomic Absorption Spectroscopy Titanium burner Specifications: Mainframe Model: AA-1800C Light Source: 6 lamps automatic turret, automatic alignment Power Supply: 110. (laboratoryspectrophotometer.com)
  • Atomic absorption spectroscopy. (perloffphoto.com)
  • This book Atomic-absorption spectrophotometry book a good source for students, specialists, and researchers conducting work on atomic absorption spectroscopy. (perloffphoto.com)
  • Show less Atomic Absorption Spectroscopy documents the proceedings of the second International Conference held at the. (perloffphoto.com)
  • Atomic Absorption Spectroscopy (AA) OF Whether your single-element inorganic analysis application Atomic-absorption spectrophotometry book flame furnace or graphite furnace Atomic-absorption spectrophotometry book absorption (AA), we offer state-of-the-art, high-performance Atomic-absorption spectrophotometry book, and support you with more than 50 years of experience as the industry leader in atomic absorption spectroscopy. (perloffphoto.com)
  • In order to understand how atomic absorption spectroscopy works, some background information is necessary. (perloffphoto.com)
  • Atomic Absorption Spectroscopy is an analytical technique used for the qualitative and quantitative determination of the elements present in different samples like food, nanomaterials, biomaterials, forensics, and industrial wastes. (perloffphoto.com)
  • Spectrophotometry is a branch of electromagnetic spectroscopy concerned with the quantitative measurement of the reflection or transmission properties of a material as a function of wavelength. (wikipedia.org)
  • Atomic Spectroscopy: Atomization. (booktopia.com.au)
  • Atomic spectroscopy (AAS and ICP-OES). (unige.it)
  • We used the analytical technique of (i) Zeeman-type electrothermal atomic absorption spectrophotometry (ETAAS) combined with (ii) preliminary analysis from the advanced photon source (APS) hard X-ray beam (7 GeV) fluorescence raster-scanning (XRFR) spectroscopy device (undulator beam line 2-ID-E) at the Argonne National Laboratory, US Department of Energy, University of Chicago IL, USA. (springer.com)
  • Your Search: (SUBJECT=Atomic absorption spectroscopy. (epa.gov)
  • perform calculations and solve problems that pertain to potentiometric methods and electroanalytical methods, spectrophotometry, atomic spectroscopy, mass spectrometry, and analytical separations. (athabascau.ca)
  • Determination of trace lithium in biological fluids using graphite furnace atomic absorption spectrophotometry: variability of urine matrices circumvented by cation exchange solid phase extraction. (unil.ch)
  • Measurements were performed using automated graphite furnace atomic absorption spectrophotometry. (nih.gov)
  • The stibine and hydrogen selenide generated are once collected by a liquid-nitrogen cold-trap, and then led, by heating the trap, into a quartz furnace for atomic absorption spectrometry. (elsevier.com)
  • Computer-Assisted Furnace Atomic Absorption Spectrometric Analysis. (epa.gov)
  • Many workers have found that this test method is reliable for sodium levels to 0.005 mg/L, but use of this test method at this low level is dependent on the configuration of the aspirator and nebulizer system available in the atomic absorption spectrophotometer as well as the experience and skill of the analyst. (bsigroup.com)
  • Then, evaluated the levels of copper using Atomic Absorption Spectrophotometer (AAS). (portalgaruda.org)
  • The trace elements were estimated using atomic absorption spectrophotometer. (bvsalud.org)
  • Fifteen essential trace and toxic elements were determined, using atomic absorption spectrophotometer. (thefreelibrary.com)
  • Ultraviolet spectrophotometry is used to show the presence of rosin or ester gum modifications in the unsaponifiable portion of an isolated alkyd coating vehicle. (dtic.mil)
  • 5.2 The major advantage of atomic absorption over atomic emission is the almost total lack of spectral interferences. (astm.org)
  • In atomic emission, the specificity of the technique is almost totally dependent on monochromator resolution. (astm.org)
  • In atomic absorption, however, the detector sees only the narrow emission lines generated by the element of interest. (astm.org)
  • Botto, R.I. (1987) Matrix Interferences in the Analysis of Organic Solutions by Inductively Coupled Plasma-Atomic Emission Spectrometry. (scirp.org)
  • All modern Perkin-Elmer atomic absorption instruments are capable of measuring both atomic absorption and atomic emission. (perloffphoto.com)
  • The theoretical importance granted to these spectroscopic results was greatly expanded upon the development of quantum mechanics, as the theory allowed for these results to be compared to atomic and molecular emission spectra which had been calculated a priori. (wikipedia.org)
  • This standard specifies a method for determining the sodium, vanadium, nickel, copper and iron content of vacuum gas oils/waxy distillates in the concentration range 0,1 mg/kg to 10 mg/kg by means of atomic absorption spectrophotometry or inductively coupled plasma emission spectrophotometry. (energyinst.org)
  • Other Atomic Emission Techniques. (booktopia.com.au)
  • Absorption and emission atomic spectrometry. (vutbr.cz)
  • An Analysis of the Concentrations of Heavy Metals in Monterey Harbor Utilizing the Methods of Atomic Absorption Spectrophotometry and Polarography. (dtic.mil)
  • The validity of atomic absorption spectrophotometry Ior measuring markers of trapped volume was checked by comparative determinations of markers with established optical spectrophotometrical methods. (bioscirep.org)
  • Atomic absorption spectrophotometric methods for the determination of oxprenolol hydrochloride, indapamide and captopril were developed. (who.int)
  • The aim of the course is to provide students with an overview of selected instrumental analytical methods from the field of electrochemistry, spectrophotometry and separation techniques and to familiarize them with their application fields and their limitations. (vutbr.cz)
  • [2] Spectrophotometry uses photometers , known as spectrophotometers, that can measure the intensity of a light beam at different wavelengths. (wikipedia.org)
  • Although spectrophotometry is most commonly applied to ultraviolet, visible , and infrared radiation, modern spectrophotometers can interrogate wide swaths of the electromagnetic spectrum , including x-ray , ultraviolet , visible , infrared , and/or microwave wavelengths. (wikipedia.org)
  • High concentrations may be diluted but preferably should be analyzed by direct aspiration atomic absorption spectrophotometry. (globalspec.com)
  • Barbooti, M. (2015) Evaluation of Analytical Procedures in the Determination of Trace Metals in Heavy Crude Oils by Flame Atomic Absorption Spectrophotometry. (scirp.org)
  • The concentration of Cu, Fe, Na, Ni, and V were determined in four heavy distillates from three heavy crude oils and one commercial crude oil by atomic absorption spectrophotometry. (osapublishing.org)
  • Then you can start reading Kindle Cited by: Techniques in Atomic Absorption Spectrophotometry Richard D. Beaty and sorption spectrophotometry. (perloffphoto.com)
  • Objectives: This paper presents a comparison study of Flame Atomic Absorption Spectrometry (FASS) and the Colorimetric method in the analysis of SZnC and hypozincemia. (uva.es)
  • Mercury in grass was quantified by atomic absorption spectrophotometry technique using hydride generator cool mist. (eia.edu.co)
  • Spectrophotometry is a useful tool in quantitative analysis where the concentration of a substance is to be identified. (reference.com)
  • Spectrophotometry is a tool that hinges on the quantitative analysis of molecules depending on how much light is absorbed by colored compounds. (wikipedia.org)
  • Complexation of Np(V) with N-methyl-iminodiacetic acid (MIDA) in 1 M NaClO{sub 4} solution was studied with multiple techniques including potentiometry, spectrophotometry, and microcalorimetry. (unt.edu)
  • Plasma samples (n = 155) of 30 patients on an intensive ward were analysed for magnesium simultaneously by atomic absorption spectrophotometry (AAS) and methylthymol blue spectrophotometry. (sigmaaldrich.com)
  • In the present work, four trace metals, V, Ni, Cu and Fe, have been determined in five crude oil samples of Eastern Baghdad area, Iraq by flame atomic absorption spectrophotometry. (scirp.org)
  • The concentrations of the metals cobalt, copper, iron, lead, and nickel in the samples were determined using atomic absorption spectrophotometry. (dtic.mil)
  • Hair samples collected from thirty-four (34) individuals in Wudil Local Government Area of Kano State Nigeria with respected to age, sex and smoking habits were analyzed for trace metals (Ca, Zn, Cu, Cd, Cr, Mg and Pb) using Atomic Absorption Spectrophotometric (AAS) technique. (alliedacademies.org)
  • Samples were analyzed using atomic absorption spectrophotometry. (cdc.gov)
  • Nabila S. Zaki, Mahmood M. Barbooti, Sulafa S. Baha-Uddin, and Eman B. Hassan, "Determination of Trace Metals and Their Distribution in Heavy Crude Oil Distillates (350°C+) by Atomic Absorption Spectrophotometry," Appl. (osapublishing.org)
  • Metals were analyzed with atomic absorption spectrophotometry. (hindawi.com)
  • This solution, or a dilution thereof, is analyzed for sodium and potassium content by atomic absorption spectrophotometry. (aaccnet.org)
  • A method is studied for the direct determination of copper in acidified urine by atomic absorption spectrophotometry. (elsevier.com)
  • The basic principle of atomic absorption spectrophotometry states that atoms absorb specific wavelengths of electromagnetic radiation. (reference.com)
  • Spectrophotometry is a measurement of how much Atomic-absorption spectrophotometry book chemical substance absorbs or transmits. (perloffphoto.com)
  • In astronomy , the term spectrophotometry refers to the measurement of the spectrum of a celestial object in which the flux scale of the spectrum is calibrated as a function of wavelength , usually by comparison with an observation of a spectrophotometric standard star, and corrected for the absorption of light by the Earth's atmosphere. (wikipedia.org)
  • Organized into seven chapters, this edition starts with an overview of the fundamental principles underlying atomic-absorption spectra. (perloffphoto.com)
  • To establish an atomic absorption spectrophotometric method for the determination of 6 heavy elements in-cluding lead,cadmium,mercury, arsenic, copper and chromium in iron filings and ferric ammonium citrate in order to control the quality and ensure people's daily medicine safety. (bvsalud.org)
  • Rao, P.D., 1972, The determination of titanium in titaniferous magnetite ores by atomic absorption spectrophotometry: University of Alaska Mineral Industry Research Laboratory AR Report 8, 2 p. (alaska.edu)
  • Indirect determination of titanium by atomic absorption spectrophotometry. (cdc.gov)
  • The amounts of complexed copper and silver were determined by atomic absorption spectrophotometry. (mdpi.com)
  • Atomic theory began with John Dalton (Figure \(\PageIndex{6}\)) in Atomic-absorption spectrophotometry book 18 th century when he proposed the concept of atoms, that all atoms of an element are identical, and that atoms of different elements can combine to form molecules. (perloffphoto.com)
  • ATOMIC ABSORPTION PROCESS While atomic absorption is the most widely applied of the three techniques and usually offers several advantages over the other two, Atomic-absorption spectrophotometry book benefits may be File Size: KB. (perloffphoto.com)
  • Summary of Atomic Techniques. (booktopia.com.au)
  • Comparison of the determination of magnesium by methylthymol blue spectrophotometry and atomic absorption spectrophotometry. (sigmaaldrich.com)
  • The major difference in the instrumentation of AAS and flame spectrophotometry is the presence of a radiation source (a particular resonance wavelength cannot be isolated from the continuous source using a prism or diffraction gratings). (blogspot.in)
  • The formation, atomic and chemical composition, evolution and fate of molecular gas clouds is of special interest, because it is from these clouds that solar systems form. (wikipedia.org)
  • Various authors (2, 3, 4, 5, 6) have investigated titanium by atomic absorption and have recommended a number of different procedures to remove interference. (alaska.edu)
  • An example of an experiment in which spectrophotometry is used is the determination of the equilibrium constant of a solution. (wikipedia.org)
  • What is the basic principle of atomic absorption spectrophotometry? (reference.com)
  • Spectrophotometry is a technique used in measuring the quantity of light absorbed by a substance by determining the intensity of light transmitted by a chemical solution. (reference.com)
  • 7. Fundamentals of optical atomic spectrometry. (vutbr.cz)
  • Dalton's atomic theory states four critical truths about atoms: firstly, everything is made up of atoms and atoms cannot be destroyed. (reference.com)
  • Determination of beryllium, cadmium, and tellurium in animal tissues using electronically excited oxygen and atomic absorption spectrophotometry. (cdc.gov)
  • A method using electronically excited oxygen for the destruction of organic matter and atomic absorption spectrophotometry for the determination of beryllium (7440417), cadmium (7440439), and tellurium (10028167) in animal tissues is presented. (cdc.gov)
  • Atomic absorption spectrophotometry assays the metal content in water. (reference.com)
  • 1.1 This practice covers general considerations for the quantitative determination of elements in water and waste water by flame atomic absorption spectrophotometry. (astm.org)
  • Flame atomic absorption spectrophotometry is simple, rapid, and applicable to a large number of elements in drinking water, surface waters, and domestic and industrial wastes. (astm.org)